<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" lang=""> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>django.db.models.query — Django 1.8.19 documentation</title> <link rel="stylesheet" href="../../../../_static/default.css" type="text/css" /> <link rel="stylesheet" href="../../../../_static/pygments.css" type="text/css" /> <script type="text/javascript"> var DOCUMENTATION_OPTIONS = { URL_ROOT: '../../../../', VERSION: '1.8.19', COLLAPSE_INDEX: false, FILE_SUFFIX: '.html', HAS_SOURCE: true }; </script> <script type="text/javascript" src="../../../../_static/jquery.js"></script> <script type="text/javascript" src="../../../../_static/underscore.js"></script> <script type="text/javascript" src="../../../../_static/doctools.js"></script> <link rel="index" title="Index" href="../../../../genindex.html" /> <link rel="search" title="Search" href="../../../../search.html" /> <link rel="top" title="Django 1.8.19 documentation" href="../../../../contents.html" /> <link rel="up" title="django" href="../../../django.html" /> <script type="text/javascript" src="../../../../templatebuiltins.js"></script> <script type="text/javascript"> (function($) { if (!django_template_builtins) { // templatebuiltins.js missing, do nothing. return; } $(document).ready(function() { // Hyperlink Django template tags and filters var base = "../../../../ref/templates/builtins.html"; if (base == "#") { // Special case for builtins.html itself base = ""; } // Tags are keywords, class '.k' $("div.highlight\\-html\\+django span.k").each(function(i, elem) { var tagname = $(elem).text(); if ($.inArray(tagname, django_template_builtins.ttags) != -1) { var fragment = tagname.replace(/_/, '-'); $(elem).html("<a href='" + base + "#" + fragment + "'>" + tagname + "</a>"); } }); // Filters are functions, class '.nf' $("div.highlight\\-html\\+django span.nf").each(function(i, elem) { var filtername = $(elem).text(); if ($.inArray(filtername, django_template_builtins.tfilters) != -1) { var fragment = filtername.replace(/_/, '-'); $(elem).html("<a href='" + base + "#" + fragment + "'>" + filtername + "</a>"); } }); }); })(jQuery); </script> </head> <body role="document"> <div class="document"> <div id="custom-doc" class="yui-t6"> <div id="hd"> <h1><a href="../../../../index.html">Django 1.8.19 documentation</a></h1> <div id="global-nav"> <a title="Home page" href="../../../../index.html">Home</a> | <a title="Table of contents" href="../../../../contents.html">Table of contents</a> | <a title="Global index" href="../../../../genindex.html">Index</a> | <a title="Module index" href="../../../../py-modindex.html">Modules</a> </div> <div class="nav"> <a href="../../../index.html" title="Module code" accesskey="U">up</a></div> </div> <div id="bd"> <div id="yui-main"> <div class="yui-b"> <div class="yui-g" id="_modules-django-db-models-query"> <h1>Source code for django.db.models.query</h1><div class="highlight"><pre> <span></span><span class="sd">"""</span> <span class="sd">The main QuerySet implementation. This provides the public API for the ORM.</span> <span class="sd">"""</span> <span class="kn">import</span> <span class="nn">copy</span> <span class="kn">import</span> <span class="nn">sys</span> <span class="kn">import</span> <span class="nn">warnings</span> <span class="kn">from</span> <span class="nn">collections</span> <span class="k">import</span> <span class="n">OrderedDict</span><span class="p">,</span> <span class="n">deque</span> <span class="kn">from</span> <span class="nn">django.conf</span> <span class="k">import</span> <span class="n">settings</span> <span class="kn">from</span> <span class="nn">django.core</span> <span class="k">import</span> <span class="n">exceptions</span> <span class="kn">from</span> <span class="nn">django.db</span> <span class="k">import</span> <span class="p">(</span> <span class="n">DJANGO_VERSION_PICKLE_KEY</span><span class="p">,</span> <span class="n">IntegrityError</span><span class="p">,</span> <span class="n">connections</span><span class="p">,</span> <span class="n">router</span><span class="p">,</span> <span class="n">transaction</span><span class="p">,</span> <span class="p">)</span> <span class="kn">from</span> <span class="nn">django.db.models</span> <span class="k">import</span> <span class="n">sql</span> <span class="kn">from</span> <span class="nn">django.db.models.constants</span> <span class="k">import</span> <span class="n">LOOKUP_SEP</span> <span class="kn">from</span> <span class="nn">django.db.models.deletion</span> <span class="k">import</span> <span class="n">Collector</span> <span class="kn">from</span> <span class="nn">django.db.models.expressions</span> <span class="k">import</span> <span class="n">Date</span><span class="p">,</span> <span class="n">DateTime</span><span class="p">,</span> <span class="n">F</span> <span class="kn">from</span> <span class="nn">django.db.models.fields</span> <span class="k">import</span> <span class="n">AutoField</span><span class="p">,</span> <span class="n">Empty</span> <span class="kn">from</span> <span class="nn">django.db.models.query_utils</span> <span class="k">import</span> <span class="p">(</span> <span class="n">InvalidQuery</span><span class="p">,</span> <span class="n">Q</span><span class="p">,</span> <span class="n">deferred_class_factory</span><span class="p">,</span> <span class="p">)</span> <span class="kn">from</span> <span class="nn">django.db.models.sql.constants</span> <span class="k">import</span> <span class="n">CURSOR</span> <span class="kn">from</span> <span class="nn">django.utils</span> <span class="k">import</span> <span class="n">six</span><span class="p">,</span> <span class="n">timezone</span> <span class="kn">from</span> <span class="nn">django.utils.functional</span> <span class="k">import</span> <span class="n">partition</span> <span class="kn">from</span> <span class="nn">django.utils.version</span> <span class="k">import</span> <span class="n">get_version</span> <span class="c1"># The maximum number of items to display in a QuerySet.__repr__</span> <span class="n">REPR_OUTPUT_SIZE</span> <span class="o">=</span> <span class="mi">20</span> <span class="c1"># Pull into this namespace for backwards compatibility.</span> <span class="n">EmptyResultSet</span> <span class="o">=</span> <span class="n">sql</span><span class="o">.</span><span class="n">EmptyResultSet</span> <span class="k">def</span> <span class="nf">_pickle_queryset</span><span class="p">(</span><span class="n">class_bases</span><span class="p">,</span> <span class="n">class_dict</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Used by `__reduce__` to create the initial version of the `QuerySet` class</span> <span class="sd"> onto which the output of `__getstate__` will be applied.</span> <span class="sd"> See `__reduce__` for more details.</span> <span class="sd"> """</span> <span class="n">new</span> <span class="o">=</span> <span class="n">Empty</span><span class="p">()</span> <span class="n">new</span><span class="o">.</span><span class="n">__class__</span> <span class="o">=</span> <span class="nb">type</span><span class="p">(</span><span class="n">class_bases</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="n">class_bases</span><span class="p">,</span> <span class="n">class_dict</span><span class="p">)</span> <span class="k">return</span> <span class="n">new</span> <div class="viewcode-block" id="QuerySet"><a class="viewcode-back" href="../../../../ref/models/querysets.html#django.db.models.query.QuerySet">[docs]</a><span class="k">class</span> <span class="nc">QuerySet</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Represents a lazy database lookup for a set of objects.</span> <span class="sd"> """</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">model</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">query</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">hints</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span> <span class="o">=</span> <span class="n">model</span> <span class="bp">self</span><span class="o">.</span><span class="n">_db</span> <span class="o">=</span> <span class="n">using</span> <span class="bp">self</span><span class="o">.</span><span class="n">_hints</span> <span class="o">=</span> <span class="n">hints</span> <span class="ow">or</span> <span class="p">{}</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span> <span class="o">=</span> <span class="n">query</span> <span class="ow">or</span> <span class="n">sql</span><span class="o">.</span><span class="n">Query</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">_sticky_filter</span> <span class="o">=</span> <span class="kc">False</span> <span class="bp">self</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="kc">False</span> <span class="bp">self</span><span class="o">.</span><span class="n">_prefetch_related_lookups</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">_prefetch_done</span> <span class="o">=</span> <span class="kc">False</span> <span class="bp">self</span><span class="o">.</span><span class="n">_known_related_objects</span> <span class="o">=</span> <span class="p">{}</span> <span class="c1"># {rel_field, {pk: rel_obj}}</span> <span class="k">def</span> <span class="nf">as_manager</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span> <span class="c1"># Address the circular dependency between `Queryset` and `Manager`.</span> <span class="kn">from</span> <span class="nn">django.db.models.manager</span> <span class="k">import</span> <span class="n">Manager</span> <span class="n">manager</span> <span class="o">=</span> <span class="n">Manager</span><span class="o">.</span><span class="n">from_queryset</span><span class="p">(</span><span class="n">cls</span><span class="p">)()</span> <span class="n">manager</span><span class="o">.</span><span class="n">_built_with_as_manager</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">return</span> <span class="n">manager</span> <span class="n">as_manager</span><span class="o">.</span><span class="n">queryset_only</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">as_manager</span> <span class="o">=</span> <span class="nb">classmethod</span><span class="p">(</span><span class="n">as_manager</span><span class="p">)</span> <span class="c1">########################</span> <span class="c1"># PYTHON MAGIC METHODS #</span> <span class="c1">########################</span> <span class="k">def</span> <span class="nf">__deepcopy__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">memo</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Deep copy of a QuerySet doesn't populate the cache</span> <span class="sd"> """</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">()</span> <span class="k">for</span> <span class="n">k</span><span class="p">,</span> <span class="n">v</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="k">if</span> <span class="n">k</span> <span class="o">==</span> <span class="s1">'_result_cache'</span><span class="p">:</span> <span class="n">obj</span><span class="o">.</span><span class="n">__dict__</span><span class="p">[</span><span class="n">k</span><span class="p">]</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">else</span><span class="p">:</span> <span class="n">obj</span><span class="o">.</span><span class="n">__dict__</span><span class="p">[</span><span class="n">k</span><span class="p">]</span> <span class="o">=</span> <span class="n">copy</span><span class="o">.</span><span class="n">deepcopy</span><span class="p">(</span><span class="n">v</span><span class="p">,</span> <span class="n">memo</span><span class="p">)</span> <span class="k">return</span> <span class="n">obj</span> <span class="k">def</span> <span class="nf">__getstate__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Allows the QuerySet to be pickled.</span> <span class="sd"> """</span> <span class="c1"># Force the cache to be fully populated.</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fetch_all</span><span class="p">()</span> <span class="n">obj_dict</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">copy</span><span class="p">()</span> <span class="n">obj_dict</span><span class="p">[</span><span class="n">DJANGO_VERSION_PICKLE_KEY</span><span class="p">]</span> <span class="o">=</span> <span class="n">get_version</span><span class="p">()</span> <span class="k">return</span> <span class="n">obj_dict</span> <span class="k">def</span> <span class="nf">__setstate__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">state</span><span class="p">):</span> <span class="n">msg</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">pickled_version</span> <span class="o">=</span> <span class="n">state</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">DJANGO_VERSION_PICKLE_KEY</span><span class="p">)</span> <span class="k">if</span> <span class="n">pickled_version</span><span class="p">:</span> <span class="n">current_version</span> <span class="o">=</span> <span class="n">get_version</span><span class="p">()</span> <span class="k">if</span> <span class="n">current_version</span> <span class="o">!=</span> <span class="n">pickled_version</span><span class="p">:</span> <span class="n">msg</span> <span class="o">=</span> <span class="p">(</span><span class="s2">"Pickled queryset instance's Django version </span><span class="si">%s</span><span class="s2"> does"</span> <span class="s2">" not match the current version </span><span class="si">%s</span><span class="s2">."</span> <span class="o">%</span> <span class="p">(</span><span class="n">pickled_version</span><span class="p">,</span> <span class="n">current_version</span><span class="p">))</span> <span class="k">else</span><span class="p">:</span> <span class="n">msg</span> <span class="o">=</span> <span class="s2">"Pickled queryset instance's Django version is not specified."</span> <span class="k">if</span> <span class="n">msg</span><span class="p">:</span> <span class="n">warnings</span><span class="o">.</span><span class="n">warn</span><span class="p">(</span><span class="n">msg</span><span class="p">,</span> <span class="ne">RuntimeWarning</span><span class="p">,</span> <span class="n">stacklevel</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">state</span><span class="p">)</span> <span class="k">def</span> <span class="nf">__reduce__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Used by pickle to deal with the types that we create dynamically when</span> <span class="sd"> specialized queryset such as `ValuesQuerySet` are used in conjunction</span> <span class="sd"> with querysets that are *subclasses* of `QuerySet`.</span> <span class="sd"> See `_clone` implementation for more details.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="s1">'_specialized_queryset_class'</span><span class="p">):</span> <span class="n">class_bases</span> <span class="o">=</span> <span class="p">(</span> <span class="bp">self</span><span class="o">.</span><span class="n">_specialized_queryset_class</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_base_queryset_class</span><span class="p">,</span> <span class="p">)</span> <span class="n">class_dict</span> <span class="o">=</span> <span class="p">{</span> <span class="s1">'_specialized_queryset_class'</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">_specialized_queryset_class</span><span class="p">,</span> <span class="s1">'_base_queryset_class'</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">_base_queryset_class</span><span class="p">,</span> <span class="p">}</span> <span class="k">return</span> <span class="n">_pickle_queryset</span><span class="p">,</span> <span class="p">(</span><span class="n">class_bases</span><span class="p">,</span> <span class="n">class_dict</span><span class="p">),</span> <span class="bp">self</span><span class="o">.</span><span class="n">__getstate__</span><span class="p">()</span> <span class="k">return</span> <span class="nb">super</span><span class="p">(</span><span class="n">QuerySet</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">__reduce__</span><span class="p">()</span> <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="n">data</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="bp">self</span><span class="p">[:</span><span class="n">REPR_OUTPUT_SIZE</span> <span class="o">+</span> <span class="mi">1</span><span class="p">])</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">data</span><span class="p">)</span> <span class="o">></span> <span class="n">REPR_OUTPUT_SIZE</span><span class="p">:</span> <span class="n">data</span><span class="p">[</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span> <span class="o">=</span> <span class="s2">"...(remaining elements truncated)..."</span> <span class="k">return</span> <span class="nb">repr</span><span class="p">(</span><span class="n">data</span><span class="p">)</span> <span class="k">def</span> <span class="nf">__len__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fetch_all</span><span class="p">()</span> <span class="k">return</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span><span class="p">)</span> <span class="k">def</span> <span class="nf">__iter__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> The queryset iterator protocol uses three nested iterators in the</span> <span class="sd"> default case:</span> <span class="sd"> 1. sql.compiler:execute_sql()</span> <span class="sd"> - Returns 100 rows at time (constants.GET_ITERATOR_CHUNK_SIZE)</span> <span class="sd"> using cursor.fetchmany(). This part is responsible for</span> <span class="sd"> doing some column masking, and returning the rows in chunks.</span> <span class="sd"> 2. sql/compiler.results_iter()</span> <span class="sd"> - Returns one row at time. At this point the rows are still just</span> <span class="sd"> tuples. In some cases the return values are converted to</span> <span class="sd"> Python values at this location.</span> <span class="sd"> 3. self.iterator()</span> <span class="sd"> - Responsible for turning the rows into model objects.</span> <span class="sd"> """</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fetch_all</span><span class="p">()</span> <span class="k">return</span> <span class="nb">iter</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span><span class="p">)</span> <span class="k">def</span> <span class="nf">__bool__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fetch_all</span><span class="p">()</span> <span class="k">return</span> <span class="nb">bool</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span><span class="p">)</span> <span class="k">def</span> <span class="nf">__nonzero__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="c1"># Python 2 compatibility</span> <span class="k">return</span> <span class="nb">type</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">__bool__</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span> <span class="k">def</span> <span class="nf">__getitem__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">k</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Retrieves an item or slice from the set of results.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">k</span><span class="p">,</span> <span class="p">(</span><span class="nb">slice</span><span class="p">,)</span> <span class="o">+</span> <span class="n">six</span><span class="o">.</span><span class="n">integer_types</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">TypeError</span> <span class="k">assert</span> <span class="p">((</span><span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">k</span><span class="p">,</span> <span class="nb">slice</span><span class="p">)</span> <span class="ow">and</span> <span class="p">(</span><span class="n">k</span> <span class="o">>=</span> <span class="mi">0</span><span class="p">))</span> <span class="ow">or</span> <span class="p">(</span><span class="nb">isinstance</span><span class="p">(</span><span class="n">k</span><span class="p">,</span> <span class="nb">slice</span><span class="p">)</span> <span class="ow">and</span> <span class="p">(</span><span class="n">k</span><span class="o">.</span><span class="n">start</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">or</span> <span class="n">k</span><span class="o">.</span><span class="n">start</span> <span class="o">>=</span> <span class="mi">0</span><span class="p">)</span> <span class="ow">and</span> <span class="p">(</span><span class="n">k</span><span class="o">.</span><span class="n">stop</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">or</span> <span class="n">k</span><span class="o">.</span><span class="n">stop</span> <span class="o">>=</span> <span class="mi">0</span><span class="p">))),</span> \ <span class="s2">"Negative indexing is not supported."</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span><span class="p">[</span><span class="n">k</span><span class="p">]</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">k</span><span class="p">,</span> <span class="nb">slice</span><span class="p">):</span> <span class="n">qs</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="k">if</span> <span class="n">k</span><span class="o">.</span><span class="n">start</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="n">start</span> <span class="o">=</span> <span class="nb">int</span><span class="p">(</span><span class="n">k</span><span class="o">.</span><span class="n">start</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">start</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">if</span> <span class="n">k</span><span class="o">.</span><span class="n">stop</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="n">stop</span> <span class="o">=</span> <span class="nb">int</span><span class="p">(</span><span class="n">k</span><span class="o">.</span><span class="n">stop</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">stop</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">qs</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">set_limits</span><span class="p">(</span><span class="n">start</span><span class="p">,</span> <span class="n">stop</span><span class="p">)</span> <span class="k">return</span> <span class="nb">list</span><span class="p">(</span><span class="n">qs</span><span class="p">)[::</span><span class="n">k</span><span class="o">.</span><span class="n">step</span><span class="p">]</span> <span class="k">if</span> <span class="n">k</span><span class="o">.</span><span class="n">step</span> <span class="k">else</span> <span class="n">qs</span> <span class="n">qs</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">qs</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">set_limits</span><span class="p">(</span><span class="n">k</span><span class="p">,</span> <span class="n">k</span> <span class="o">+</span> <span class="mi">1</span><span class="p">)</span> <span class="k">return</span> <span class="nb">list</span><span class="p">(</span><span class="n">qs</span><span class="p">)[</span><span class="mi">0</span><span class="p">]</span> <span class="k">def</span> <span class="nf">__and__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">_merge_sanity_check</span><span class="p">(</span><span class="n">other</span><span class="p">)</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">other</span><span class="p">,</span> <span class="n">EmptyQuerySet</span><span class="p">):</span> <span class="k">return</span> <span class="n">other</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">EmptyQuerySet</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span> <span class="n">combined</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">combined</span><span class="o">.</span><span class="n">_merge_known_related_objects</span><span class="p">(</span><span class="n">other</span><span class="p">)</span> <span class="n">combined</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">combine</span><span class="p">(</span><span class="n">other</span><span class="o">.</span><span class="n">query</span><span class="p">,</span> <span class="n">sql</span><span class="o">.</span><span class="n">AND</span><span class="p">)</span> <span class="k">return</span> <span class="n">combined</span> <span class="k">def</span> <span class="nf">__or__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">_merge_sanity_check</span><span class="p">(</span><span class="n">other</span><span class="p">)</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">EmptyQuerySet</span><span class="p">):</span> <span class="k">return</span> <span class="n">other</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">other</span><span class="p">,</span> <span class="n">EmptyQuerySet</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span> <span class="n">combined</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">combined</span><span class="o">.</span><span class="n">_merge_known_related_objects</span><span class="p">(</span><span class="n">other</span><span class="p">)</span> <span class="n">combined</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">combine</span><span class="p">(</span><span class="n">other</span><span class="o">.</span><span class="n">query</span><span class="p">,</span> <span class="n">sql</span><span class="o">.</span><span class="n">OR</span><span class="p">)</span> <span class="k">return</span> <span class="n">combined</span> <span class="c1">####################################</span> <span class="c1"># METHODS THAT DO DATABASE QUERIES #</span> <span class="c1">####################################</span> <span class="k">def</span> <span class="nf">iterator</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> An iterator over the results from applying this QuerySet to the</span> <span class="sd"> database.</span> <span class="sd"> """</span> <span class="n">db</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">db</span> <span class="n">compiler</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">get_compiler</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="n">db</span><span class="p">)</span> <span class="c1"># Execute the query. This will also fill compiler.select, klass_info,</span> <span class="c1"># and annotations.</span> <span class="n">results</span> <span class="o">=</span> <span class="n">compiler</span><span class="o">.</span><span class="n">execute_sql</span><span class="p">()</span> <span class="n">select</span><span class="p">,</span> <span class="n">klass_info</span><span class="p">,</span> <span class="n">annotation_col_map</span> <span class="o">=</span> <span class="p">(</span><span class="n">compiler</span><span class="o">.</span><span class="n">select</span><span class="p">,</span> <span class="n">compiler</span><span class="o">.</span><span class="n">klass_info</span><span class="p">,</span> <span class="n">compiler</span><span class="o">.</span><span class="n">annotation_col_map</span><span class="p">)</span> <span class="k">if</span> <span class="n">klass_info</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">return</span> <span class="n">model_cls</span> <span class="o">=</span> <span class="n">klass_info</span><span class="p">[</span><span class="s1">'model'</span><span class="p">]</span> <span class="n">select_fields</span> <span class="o">=</span> <span class="n">klass_info</span><span class="p">[</span><span class="s1">'select_fields'</span><span class="p">]</span> <span class="n">model_fields_start</span><span class="p">,</span> <span class="n">model_fields_end</span> <span class="o">=</span> <span class="n">select_fields</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span> <span class="n">select_fields</span><span class="p">[</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span> <span class="o">+</span> <span class="mi">1</span> <span class="n">init_list</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span><span class="o">.</span><span class="n">target</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">select</span><span class="p">[</span><span class="n">model_fields_start</span><span class="p">:</span><span class="n">model_fields_end</span><span class="p">]]</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">init_list</span><span class="p">)</span> <span class="o">!=</span> <span class="nb">len</span><span class="p">(</span><span class="n">model_cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">):</span> <span class="n">init_set</span> <span class="o">=</span> <span class="nb">set</span><span class="p">(</span><span class="n">init_list</span><span class="p">)</span> <span class="n">skip</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">model_cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">init_set</span><span class="p">]</span> <span class="n">model_cls</span> <span class="o">=</span> <span class="n">deferred_class_factory</span><span class="p">(</span><span class="n">model_cls</span><span class="p">,</span> <span class="n">skip</span><span class="p">)</span> <span class="n">related_populators</span> <span class="o">=</span> <span class="n">get_related_populators</span><span class="p">(</span><span class="n">klass_info</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">db</span><span class="p">)</span> <span class="k">for</span> <span class="n">row</span> <span class="ow">in</span> <span class="n">compiler</span><span class="o">.</span><span class="n">results_iter</span><span class="p">(</span><span class="n">results</span><span class="p">):</span> <span class="n">obj</span> <span class="o">=</span> <span class="n">model_cls</span><span class="o">.</span><span class="n">from_db</span><span class="p">(</span><span class="n">db</span><span class="p">,</span> <span class="n">init_list</span><span class="p">,</span> <span class="n">row</span><span class="p">[</span><span class="n">model_fields_start</span><span class="p">:</span><span class="n">model_fields_end</span><span class="p">])</span> <span class="k">if</span> <span class="n">related_populators</span><span class="p">:</span> <span class="k">for</span> <span class="n">rel_populator</span> <span class="ow">in</span> <span class="n">related_populators</span><span class="p">:</span> <span class="n">rel_populator</span><span class="o">.</span><span class="n">populate</span><span class="p">(</span><span class="n">row</span><span class="p">,</span> <span class="n">obj</span><span class="p">)</span> <span class="k">if</span> <span class="n">annotation_col_map</span><span class="p">:</span> <span class="k">for</span> <span class="n">attr_name</span><span class="p">,</span> <span class="n">col_pos</span> <span class="ow">in</span> <span class="n">annotation_col_map</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">attr_name</span><span class="p">,</span> <span class="n">row</span><span class="p">[</span><span class="n">col_pos</span><span class="p">])</span> <span class="c1"># Add the known related objects to the model, if there are any</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_known_related_objects</span><span class="p">:</span> <span class="k">for</span> <span class="n">field</span><span class="p">,</span> <span class="n">rel_objs</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_known_related_objects</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="c1"># Avoid overwriting objects loaded e.g. by select_related</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">()):</span> <span class="k">continue</span> <span class="n">pk</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">get_attname</span><span class="p">())</span> <span class="k">try</span><span class="p">:</span> <span class="n">rel_obj</span> <span class="o">=</span> <span class="n">rel_objs</span><span class="p">[</span><span class="n">pk</span><span class="p">]</span> <span class="k">except</span> <span class="ne">KeyError</span><span class="p">:</span> <span class="k">pass</span> <span class="c1"># may happen in qs1 | qs2 scenarios</span> <span class="k">else</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">name</span><span class="p">,</span> <span class="n">rel_obj</span><span class="p">)</span> <span class="k">yield</span> <span class="n">obj</span> <span class="k">def</span> <span class="nf">aggregate</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a dictionary containing the calculations (aggregation)</span> <span class="sd"> over the current queryset</span> <span class="sd"> If args is present the expression is passed as a kwarg using</span> <span class="sd"> the Aggregate object's default alias.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">distinct_fields</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">NotImplementedError</span><span class="p">(</span><span class="s2">"aggregate() + distinct(fields) not implemented."</span><span class="p">)</span> <span class="k">for</span> <span class="n">arg</span> <span class="ow">in</span> <span class="n">args</span><span class="p">:</span> <span class="c1"># The default_alias property may raise a TypeError, so we use</span> <span class="c1"># a try/except construct rather than hasattr in order to remain</span> <span class="c1"># consistent between PY2 and PY3 (hasattr would swallow</span> <span class="c1"># the TypeError on PY2).</span> <span class="k">try</span><span class="p">:</span> <span class="n">arg</span><span class="o">.</span><span class="n">default_alias</span> <span class="k">except</span> <span class="p">(</span><span class="ne">AttributeError</span><span class="p">,</span> <span class="ne">TypeError</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"Complex aggregates require an alias"</span><span class="p">)</span> <span class="n">kwargs</span><span class="p">[</span><span class="n">arg</span><span class="o">.</span><span class="n">default_alias</span><span class="p">]</span> <span class="o">=</span> <span class="n">arg</span> <span class="n">query</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clone</span><span class="p">()</span> <span class="k">for</span> <span class="p">(</span><span class="n">alias</span><span class="p">,</span> <span class="n">aggregate_expr</span><span class="p">)</span> <span class="ow">in</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="n">query</span><span class="o">.</span><span class="n">add_annotation</span><span class="p">(</span><span class="n">aggregate_expr</span><span class="p">,</span> <span class="n">alias</span><span class="p">,</span> <span class="n">is_summary</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">query</span><span class="o">.</span><span class="n">annotations</span><span class="p">[</span><span class="n">alias</span><span class="p">]</span><span class="o">.</span><span class="n">contains_aggregate</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"</span><span class="si">%s</span><span class="s2"> is not an aggregate expression"</span> <span class="o">%</span> <span class="n">alias</span><span class="p">)</span> <span class="k">return</span> <span class="n">query</span><span class="o">.</span><span class="n">get_aggregation</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">,</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">keys</span><span class="p">())</span> <span class="k">def</span> <span class="nf">count</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Performs a SELECT COUNT() and returns the number of records as an</span> <span class="sd"> integer.</span> <span class="sd"> If the QuerySet is already fully cached this simply returns the length</span> <span class="sd"> of the cached results set to avoid multiple SELECT COUNT(*) calls.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="k">return</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span><span class="p">)</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">get_count</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Performs the query and returns a single object matching the given</span> <span class="sd"> keyword arguments.</span> <span class="sd"> """</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">():</span> <span class="n">clone</span> <span class="o">=</span> <span class="n">clone</span><span class="o">.</span><span class="n">order_by</span><span class="p">()</span> <span class="n">num</span> <span class="o">=</span> <span class="nb">len</span><span class="p">(</span><span class="n">clone</span><span class="p">)</span> <span class="k">if</span> <span class="n">num</span> <span class="o">==</span> <span class="mi">1</span><span class="p">:</span> <span class="k">return</span> <span class="n">clone</span><span class="o">.</span><span class="n">_result_cache</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">num</span><span class="p">:</span> <span class="k">raise</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">DoesNotExist</span><span class="p">(</span> <span class="s2">"</span><span class="si">%s</span><span class="s2"> matching query does not exist."</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span> <span class="p">)</span> <span class="k">raise</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">MultipleObjectsReturned</span><span class="p">(</span> <span class="s2">"get() returned more than one </span><span class="si">%s</span><span class="s2"> -- it returned </span><span class="si">%s</span><span class="s2">!"</span> <span class="o">%</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">object_name</span><span class="p">,</span> <span class="n">num</span><span class="p">)</span> <span class="p">)</span> <span class="k">def</span> <span class="nf">create</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Creates a new object with the given kwargs, saving it to the database</span> <span class="sd"> and returning the created object.</span> <span class="sd"> """</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">(</span><span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">obj</span><span class="o">.</span><span class="n">save</span><span class="p">(</span><span class="n">force_insert</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span> <span class="k">return</span> <span class="n">obj</span> <span class="k">def</span> <span class="nf">_populate_pk_values</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">objs</span><span class="p">):</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">objs</span><span class="p">:</span> <span class="k">if</span> <span class="n">obj</span><span class="o">.</span><span class="n">pk</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">obj</span><span class="o">.</span><span class="n">pk</span> <span class="o">=</span> <span class="n">obj</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">get_pk_value_on_save</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span> <span class="k">def</span> <span class="nf">bulk_create</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">objs</span><span class="p">,</span> <span class="n">batch_size</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Inserts each of the instances into the database. This does *not* call</span> <span class="sd"> save() on each of the instances, does not send any pre/post save</span> <span class="sd"> signals, and does not set the primary key attribute if it is an</span> <span class="sd"> autoincrement field.</span> <span class="sd"> """</span> <span class="c1"># So this case is fun. When you bulk insert you don't get the primary</span> <span class="c1"># keys back (if it's an autoincrement), so you can't insert into the</span> <span class="c1"># child tables which references this. There are two workarounds, 1)</span> <span class="c1"># this could be implemented if you didn't have an autoincrement pk,</span> <span class="c1"># and 2) you could do it by doing O(n) normal inserts into the parent</span> <span class="c1"># tables to get the primary keys back, and then doing a single bulk</span> <span class="c1"># insert into the childmost table. Some databases might allow doing</span> <span class="c1"># this by using RETURNING clause for the insert query. We're punting</span> <span class="c1"># on these for now because they are relatively rare cases.</span> <span class="k">assert</span> <span class="n">batch_size</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">or</span> <span class="n">batch_size</span> <span class="o">></span> <span class="mi">0</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">parents</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"Can't bulk create an inherited model"</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">objs</span><span class="p">:</span> <span class="k">return</span> <span class="n">objs</span> <span class="bp">self</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">connection</span> <span class="o">=</span> <span class="n">connections</span><span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">]</span> <span class="n">fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">local_concrete_fields</span> <span class="n">objs</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">objs</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_populate_pk_values</span><span class="p">(</span><span class="n">objs</span><span class="p">)</span> <span class="k">with</span> <span class="n">transaction</span><span class="o">.</span><span class="n">atomic</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">,</span> <span class="n">savepoint</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="k">if</span> <span class="p">(</span><span class="n">connection</span><span class="o">.</span><span class="n">features</span><span class="o">.</span><span class="n">can_combine_inserts_with_and_without_auto_increment_pk</span> <span class="ow">and</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">has_auto_field</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">_batched_insert</span><span class="p">(</span><span class="n">objs</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="n">batch_size</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">objs_with_pk</span><span class="p">,</span> <span class="n">objs_without_pk</span> <span class="o">=</span> <span class="n">partition</span><span class="p">(</span><span class="k">lambda</span> <span class="n">o</span><span class="p">:</span> <span class="n">o</span><span class="o">.</span><span class="n">pk</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">,</span> <span class="n">objs</span><span class="p">)</span> <span class="k">if</span> <span class="n">objs_with_pk</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">_batched_insert</span><span class="p">(</span><span class="n">objs_with_pk</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="n">batch_size</span><span class="p">)</span> <span class="k">if</span> <span class="n">objs_without_pk</span><span class="p">:</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">f</span><span class="p">,</span> <span class="n">AutoField</span><span class="p">)]</span> <span class="bp">self</span><span class="o">.</span><span class="n">_batched_insert</span><span class="p">(</span><span class="n">objs_without_pk</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="n">batch_size</span><span class="p">)</span> <span class="k">return</span> <span class="n">objs</span> <span class="k">def</span> <span class="nf">get_or_create</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">defaults</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Looks up an object with the given kwargs, creating one if necessary.</span> <span class="sd"> Returns a tuple of (object, created), where created is a boolean</span> <span class="sd"> specifying whether an object was created.</span> <span class="sd"> """</span> <span class="n">lookup</span><span class="p">,</span> <span class="n">params</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_extract_model_params</span><span class="p">(</span><span class="n">defaults</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">try</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="o">**</span><span class="n">lookup</span><span class="p">),</span> <span class="kc">False</span> <span class="k">except</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">DoesNotExist</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_create_object_from_params</span><span class="p">(</span><span class="n">lookup</span><span class="p">,</span> <span class="n">params</span><span class="p">)</span> <span class="k">def</span> <span class="nf">update_or_create</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">defaults</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Looks up an object with the given kwargs, updating one with defaults</span> <span class="sd"> if it exists, otherwise creates a new one.</span> <span class="sd"> Returns a tuple (object, created), where created is a boolean</span> <span class="sd"> specifying whether an object was created.</span> <span class="sd"> """</span> <span class="n">defaults</span> <span class="o">=</span> <span class="n">defaults</span> <span class="ow">or</span> <span class="p">{}</span> <span class="n">lookup</span><span class="p">,</span> <span class="n">params</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_extract_model_params</span><span class="p">(</span><span class="n">defaults</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">try</span><span class="p">:</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="o">**</span><span class="n">lookup</span><span class="p">)</span> <span class="k">except</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">DoesNotExist</span><span class="p">:</span> <span class="n">obj</span><span class="p">,</span> <span class="n">created</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_create_object_from_params</span><span class="p">(</span><span class="n">lookup</span><span class="p">,</span> <span class="n">params</span><span class="p">)</span> <span class="k">if</span> <span class="n">created</span><span class="p">:</span> <span class="k">return</span> <span class="n">obj</span><span class="p">,</span> <span class="n">created</span> <span class="k">for</span> <span class="n">k</span><span class="p">,</span> <span class="n">v</span> <span class="ow">in</span> <span class="n">six</span><span class="o">.</span><span class="n">iteritems</span><span class="p">(</span><span class="n">defaults</span><span class="p">):</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">k</span><span class="p">,</span> <span class="n">v</span><span class="p">)</span> <span class="k">with</span> <span class="n">transaction</span><span class="o">.</span><span class="n">atomic</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">,</span> <span class="n">savepoint</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="n">obj</span><span class="o">.</span><span class="n">save</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span> <span class="k">return</span> <span class="n">obj</span><span class="p">,</span> <span class="kc">False</span> <span class="k">def</span> <span class="nf">_create_object_from_params</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">lookup</span><span class="p">,</span> <span class="n">params</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Tries to create an object using passed params.</span> <span class="sd"> Used by get_or_create and update_or_create</span> <span class="sd"> """</span> <span class="k">try</span><span class="p">:</span> <span class="k">with</span> <span class="n">transaction</span><span class="o">.</span><span class="n">atomic</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">):</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">create</span><span class="p">(</span><span class="o">**</span><span class="n">params</span><span class="p">)</span> <span class="k">return</span> <span class="n">obj</span><span class="p">,</span> <span class="kc">True</span> <span class="k">except</span> <span class="n">IntegrityError</span><span class="p">:</span> <span class="n">exc_info</span> <span class="o">=</span> <span class="n">sys</span><span class="o">.</span><span class="n">exc_info</span><span class="p">()</span> <span class="k">try</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="o">**</span><span class="n">lookup</span><span class="p">),</span> <span class="kc">False</span> <span class="k">except</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">DoesNotExist</span><span class="p">:</span> <span class="k">pass</span> <span class="n">six</span><span class="o">.</span><span class="n">reraise</span><span class="p">(</span><span class="o">*</span><span class="n">exc_info</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_extract_model_params</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">defaults</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Prepares `lookup` (kwargs that are valid model attributes), `params`</span> <span class="sd"> (for creating a model instance) based on given kwargs; for use by</span> <span class="sd"> get_or_create and update_or_create.</span> <span class="sd"> """</span> <span class="n">defaults</span> <span class="o">=</span> <span class="n">defaults</span> <span class="ow">or</span> <span class="p">{}</span> <span class="n">lookup</span> <span class="o">=</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">copy</span><span class="p">()</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">:</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="ow">in</span> <span class="n">lookup</span><span class="p">:</span> <span class="n">lookup</span><span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">name</span><span class="p">]</span> <span class="o">=</span> <span class="n">lookup</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="n">params</span> <span class="o">=</span> <span class="p">{</span><span class="n">k</span><span class="p">:</span> <span class="n">v</span> <span class="k">for</span> <span class="n">k</span><span class="p">,</span> <span class="n">v</span> <span class="ow">in</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">items</span><span class="p">()</span> <span class="k">if</span> <span class="n">LOOKUP_SEP</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">k</span><span class="p">}</span> <span class="n">params</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">defaults</span><span class="p">)</span> <span class="k">return</span> <span class="n">lookup</span><span class="p">,</span> <span class="n">params</span> <span class="k">def</span> <span class="nf">_earliest_or_latest</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field_name</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">direction</span><span class="o">=</span><span class="s2">"-"</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns the latest object, according to the model's</span> <span class="sd"> 'get_latest_by' option or optional given field_name.</span> <span class="sd"> """</span> <span class="n">order_by</span> <span class="o">=</span> <span class="n">field_name</span> <span class="ow">or</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="p">,</span> <span class="s1">'get_latest_by'</span><span class="p">)</span> <span class="k">assert</span> <span class="nb">bool</span><span class="p">(</span><span class="n">order_by</span><span class="p">),</span> <span class="s2">"earliest() and latest() require either a "</span>\ <span class="s2">"field_name parameter or 'get_latest_by' in the model"</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">(),</span> \ <span class="s2">"Cannot change a query once a slice has been taken."</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">set_limits</span><span class="p">(</span><span class="n">high</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clear_ordering</span><span class="p">(</span><span class="n">force_empty</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_ordering</span><span class="p">(</span><span class="s1">'</span><span class="si">%s%s</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="n">direction</span><span class="p">,</span> <span class="n">order_by</span><span class="p">))</span> <span class="k">return</span> <span class="n">obj</span><span class="o">.</span><span class="n">get</span><span class="p">()</span> <span class="k">def</span> <span class="nf">earliest</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field_name</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_earliest_or_latest</span><span class="p">(</span><span class="n">field_name</span><span class="o">=</span><span class="n">field_name</span><span class="p">,</span> <span class="n">direction</span><span class="o">=</span><span class="s2">""</span><span class="p">)</span> <span class="k">def</span> <span class="nf">latest</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field_name</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_earliest_or_latest</span><span class="p">(</span><span class="n">field_name</span><span class="o">=</span><span class="n">field_name</span><span class="p">,</span> <span class="n">direction</span><span class="o">=</span><span class="s2">"-"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">first</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns the first object of a query, returns None if no match is found.</span> <span class="sd"> """</span> <span class="n">objects</span> <span class="o">=</span> <span class="nb">list</span><span class="p">((</span><span class="bp">self</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">ordered</span> <span class="k">else</span> <span class="bp">self</span><span class="o">.</span><span class="n">order_by</span><span class="p">(</span><span class="s1">'pk'</span><span class="p">))[:</span><span class="mi">1</span><span class="p">])</span> <span class="k">if</span> <span class="n">objects</span><span class="p">:</span> <span class="k">return</span> <span class="n">objects</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">return</span> <span class="kc">None</span> <span class="k">def</span> <span class="nf">last</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns the last object of a query, returns None if no match is found.</span> <span class="sd"> """</span> <span class="n">objects</span> <span class="o">=</span> <span class="nb">list</span><span class="p">((</span><span class="bp">self</span><span class="o">.</span><span class="n">reverse</span><span class="p">()</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">ordered</span> <span class="k">else</span> <span class="bp">self</span><span class="o">.</span><span class="n">order_by</span><span class="p">(</span><span class="s1">'-pk'</span><span class="p">))[:</span><span class="mi">1</span><span class="p">])</span> <span class="k">if</span> <span class="n">objects</span><span class="p">:</span> <span class="k">return</span> <span class="n">objects</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">return</span> <span class="kc">None</span> <span class="k">def</span> <span class="nf">in_bulk</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">id_list</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a dictionary mapping each of the given IDs to the object with</span> <span class="sd"> that ID.</span> <span class="sd"> """</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">(),</span> \ <span class="s2">"Cannot use 'limit' or 'offset' with in_bulk"</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">id_list</span><span class="p">:</span> <span class="k">return</span> <span class="p">{}</span> <span class="n">qs</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">pk__in</span><span class="o">=</span><span class="n">id_list</span><span class="p">)</span><span class="o">.</span><span class="n">order_by</span><span class="p">()</span> <span class="k">return</span> <span class="p">{</span><span class="n">obj</span><span class="o">.</span><span class="n">_get_pk_val</span><span class="p">():</span> <span class="n">obj</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">qs</span><span class="p">}</span> <span class="k">def</span> <span class="nf">delete</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Deletes the records in the current QuerySet.</span> <span class="sd"> """</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">(),</span> \ <span class="s2">"Cannot use 'limit' or 'offset' with delete."</span> <span class="n">del_query</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="c1"># The delete is actually 2 queries - one to find related objects,</span> <span class="c1"># and one to delete. Make sure that the discovery of related</span> <span class="c1"># objects is performed on the same database as the deletion.</span> <span class="n">del_query</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="kc">True</span> <span class="c1"># Disable non-supported fields.</span> <span class="n">del_query</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">select_for_update</span> <span class="o">=</span> <span class="kc">False</span> <span class="n">del_query</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">select_related</span> <span class="o">=</span> <span class="kc">False</span> <span class="n">del_query</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clear_ordering</span><span class="p">(</span><span class="n">force_empty</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span> <span class="n">collector</span> <span class="o">=</span> <span class="n">Collector</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="n">del_query</span><span class="o">.</span><span class="n">db</span><span class="p">)</span> <span class="n">collector</span><span class="o">.</span><span class="n">collect</span><span class="p">(</span><span class="n">del_query</span><span class="p">)</span> <span class="n">collector</span><span class="o">.</span><span class="n">delete</span><span class="p">()</span> <span class="c1"># Clear the result cache, in case this QuerySet gets reused.</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">delete</span><span class="o">.</span><span class="n">alters_data</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">delete</span><span class="o">.</span><span class="n">queryset_only</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">def</span> <span class="nf">_raw_delete</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">using</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Deletes objects found from the given queryset in single direct SQL</span> <span class="sd"> query. No signals are sent, and there is no protection for cascades.</span> <span class="sd"> """</span> <span class="n">sql</span><span class="o">.</span><span class="n">DeleteQuery</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">)</span><span class="o">.</span><span class="n">delete_qs</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">using</span><span class="p">)</span> <span class="n">_raw_delete</span><span class="o">.</span><span class="n">alters_data</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">def</span> <span class="nf">update</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Updates all elements in the current QuerySet, setting all the given</span> <span class="sd"> fields to the appropriate values.</span> <span class="sd"> """</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">(),</span> \ <span class="s2">"Cannot update a query once a slice has been taken."</span> <span class="bp">self</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">query</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clone</span><span class="p">(</span><span class="n">sql</span><span class="o">.</span><span class="n">UpdateQuery</span><span class="p">)</span> <span class="n">query</span><span class="o">.</span><span class="n">add_update_values</span><span class="p">(</span><span class="n">kwargs</span><span class="p">)</span> <span class="k">with</span> <span class="n">transaction</span><span class="o">.</span><span class="n">atomic</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">,</span> <span class="n">savepoint</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="n">rows</span> <span class="o">=</span> <span class="n">query</span><span class="o">.</span><span class="n">get_compiler</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span><span class="o">.</span><span class="n">execute_sql</span><span class="p">(</span><span class="n">CURSOR</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">return</span> <span class="n">rows</span> <span class="n">update</span><span class="o">.</span><span class="n">alters_data</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">def</span> <span class="nf">_update</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">values</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> A version of update that accepts field objects instead of field names.</span> <span class="sd"> Used primarily for model saving and not intended for use by general</span> <span class="sd"> code (it requires too much poking around at model internals to be</span> <span class="sd"> useful at that level).</span> <span class="sd"> """</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">(),</span> \ <span class="s2">"Cannot update a query once a slice has been taken."</span> <span class="n">query</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clone</span><span class="p">(</span><span class="n">sql</span><span class="o">.</span><span class="n">UpdateQuery</span><span class="p">)</span> <span class="n">query</span><span class="o">.</span><span class="n">add_update_fields</span><span class="p">(</span><span class="n">values</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">return</span> <span class="n">query</span><span class="o">.</span><span class="n">get_compiler</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span><span class="o">.</span><span class="n">execute_sql</span><span class="p">(</span><span class="n">CURSOR</span><span class="p">)</span> <span class="n">_update</span><span class="o">.</span><span class="n">alters_data</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">_update</span><span class="o">.</span><span class="n">queryset_only</span> <span class="o">=</span> <span class="kc">False</span> <span class="k">def</span> <span class="nf">exists</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">has_results</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span> <span class="k">return</span> <span class="nb">bool</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_prefetch_related_objects</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="c1"># This method can only be called once the result cache has been filled.</span> <span class="n">prefetch_related_objects</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">_prefetch_related_lookups</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_prefetch_done</span> <span class="o">=</span> <span class="kc">True</span> <span class="c1">##################################################</span> <span class="c1"># PUBLIC METHODS THAT RETURN A QUERYSET SUBCLASS #</span> <span class="c1">##################################################</span> <span class="k">def</span> <span class="nf">raw</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">raw_query</span><span class="p">,</span> <span class="n">params</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">translations</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="k">if</span> <span class="n">using</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">using</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">db</span> <span class="k">return</span> <span class="n">RawQuerySet</span><span class="p">(</span><span class="n">raw_query</span><span class="p">,</span> <span class="n">model</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">,</span> <span class="n">params</span><span class="o">=</span><span class="n">params</span><span class="p">,</span> <span class="n">translations</span><span class="o">=</span><span class="n">translations</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">)</span> <span class="k">def</span> <span class="nf">values</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">fields</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">(</span><span class="n">klass</span><span class="o">=</span><span class="n">ValuesQuerySet</span><span class="p">,</span> <span class="n">setup</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">_fields</span><span class="o">=</span><span class="n">fields</span><span class="p">)</span> <span class="k">def</span> <span class="nf">values_list</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">fields</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="n">flat</span> <span class="o">=</span> <span class="n">kwargs</span><span class="o">.</span><span class="n">pop</span><span class="p">(</span><span class="s1">'flat'</span><span class="p">,</span> <span class="kc">False</span><span class="p">)</span> <span class="k">if</span> <span class="n">kwargs</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s1">'Unexpected keyword arguments to values_list: </span><span class="si">%s</span><span class="s1">'</span> <span class="o">%</span> <span class="p">(</span><span class="nb">list</span><span class="p">(</span><span class="n">kwargs</span><span class="p">),))</span> <span class="k">if</span> <span class="n">flat</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="n">fields</span><span class="p">)</span> <span class="o">></span> <span class="mi">1</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"'flat' is not valid when values_list is called with more than one field."</span><span class="p">)</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">(</span><span class="n">klass</span><span class="o">=</span><span class="n">ValuesListQuerySet</span><span class="p">,</span> <span class="n">setup</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span> <span class="n">flat</span><span class="o">=</span><span class="n">flat</span><span class="p">,</span> <span class="n">_fields</span><span class="o">=</span><span class="n">fields</span><span class="p">)</span> <span class="k">def</span> <span class="nf">dates</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field_name</span><span class="p">,</span> <span class="n">kind</span><span class="p">,</span> <span class="n">order</span><span class="o">=</span><span class="s1">'ASC'</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a list of date objects representing all available dates for</span> <span class="sd"> the given field_name, scoped to 'kind'.</span> <span class="sd"> """</span> <span class="k">assert</span> <span class="n">kind</span> <span class="ow">in</span> <span class="p">(</span><span class="s2">"year"</span><span class="p">,</span> <span class="s2">"month"</span><span class="p">,</span> <span class="s2">"day"</span><span class="p">),</span> \ <span class="s2">"'kind' must be one of 'year', 'month' or 'day'."</span> <span class="k">assert</span> <span class="n">order</span> <span class="ow">in</span> <span class="p">(</span><span class="s1">'ASC'</span><span class="p">,</span> <span class="s1">'DESC'</span><span class="p">),</span> \ <span class="s2">"'order' must be either 'ASC' or 'DESC'."</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotate</span><span class="p">(</span> <span class="n">datefield</span><span class="o">=</span><span class="n">Date</span><span class="p">(</span><span class="n">field_name</span><span class="p">,</span> <span class="n">kind</span><span class="p">),</span> <span class="n">plain_field</span><span class="o">=</span><span class="n">F</span><span class="p">(</span><span class="n">field_name</span><span class="p">)</span> <span class="p">)</span><span class="o">.</span><span class="n">values_list</span><span class="p">(</span> <span class="s1">'datefield'</span><span class="p">,</span> <span class="n">flat</span><span class="o">=</span><span class="kc">True</span> <span class="p">)</span><span class="o">.</span><span class="n">distinct</span><span class="p">()</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">plain_field__isnull</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span><span class="o">.</span><span class="n">order_by</span><span class="p">((</span><span class="s1">'-'</span> <span class="k">if</span> <span class="n">order</span> <span class="o">==</span> <span class="s1">'DESC'</span> <span class="k">else</span> <span class="s1">''</span><span class="p">)</span> <span class="o">+</span> <span class="s1">'datefield'</span><span class="p">)</span> <span class="k">def</span> <span class="nf">datetimes</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">field_name</span><span class="p">,</span> <span class="n">kind</span><span class="p">,</span> <span class="n">order</span><span class="o">=</span><span class="s1">'ASC'</span><span class="p">,</span> <span class="n">tzinfo</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a list of datetime objects representing all available</span> <span class="sd"> datetimes for the given field_name, scoped to 'kind'.</span> <span class="sd"> """</span> <span class="k">assert</span> <span class="n">kind</span> <span class="ow">in</span> <span class="p">(</span><span class="s2">"year"</span><span class="p">,</span> <span class="s2">"month"</span><span class="p">,</span> <span class="s2">"day"</span><span class="p">,</span> <span class="s2">"hour"</span><span class="p">,</span> <span class="s2">"minute"</span><span class="p">,</span> <span class="s2">"second"</span><span class="p">),</span> \ <span class="s2">"'kind' must be one of 'year', 'month', 'day', 'hour', 'minute' or 'second'."</span> <span class="k">assert</span> <span class="n">order</span> <span class="ow">in</span> <span class="p">(</span><span class="s1">'ASC'</span><span class="p">,</span> <span class="s1">'DESC'</span><span class="p">),</span> \ <span class="s2">"'order' must be either 'ASC' or 'DESC'."</span> <span class="k">if</span> <span class="n">settings</span><span class="o">.</span><span class="n">USE_TZ</span><span class="p">:</span> <span class="k">if</span> <span class="n">tzinfo</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">tzinfo</span> <span class="o">=</span> <span class="n">timezone</span><span class="o">.</span><span class="n">get_current_timezone</span><span class="p">()</span> <span class="k">else</span><span class="p">:</span> <span class="n">tzinfo</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotate</span><span class="p">(</span> <span class="n">datetimefield</span><span class="o">=</span><span class="n">DateTime</span><span class="p">(</span><span class="n">field_name</span><span class="p">,</span> <span class="n">kind</span><span class="p">,</span> <span class="n">tzinfo</span><span class="p">),</span> <span class="n">plain_field</span><span class="o">=</span><span class="n">F</span><span class="p">(</span><span class="n">field_name</span><span class="p">)</span> <span class="p">)</span><span class="o">.</span><span class="n">values_list</span><span class="p">(</span> <span class="s1">'datetimefield'</span><span class="p">,</span> <span class="n">flat</span><span class="o">=</span><span class="kc">True</span> <span class="p">)</span><span class="o">.</span><span class="n">distinct</span><span class="p">()</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">plain_field__isnull</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span><span class="o">.</span><span class="n">order_by</span><span class="p">((</span><span class="s1">'-'</span> <span class="k">if</span> <span class="n">order</span> <span class="o">==</span> <span class="s1">'DESC'</span> <span class="k">else</span> <span class="s1">''</span><span class="p">)</span> <span class="o">+</span> <span class="s1">'datetimefield'</span><span class="p">)</span> <span class="k">def</span> <span class="nf">none</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns an empty QuerySet.</span> <span class="sd"> """</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">set_empty</span><span class="p">()</span> <span class="k">return</span> <span class="n">clone</span> <span class="c1">##################################################################</span> <span class="c1"># PUBLIC METHODS THAT ALTER ATTRIBUTES AND RETURN A NEW QUERYSET #</span> <span class="c1">##################################################################</span> <span class="k">def</span> <span class="nf">all</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a new QuerySet that is a copy of the current one. This allows a</span> <span class="sd"> QuerySet to proxy for a model manager in some cases.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="k">def</span> <span class="nf">filter</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a new QuerySet instance with the args ANDed to the existing</span> <span class="sd"> set.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_filter_or_exclude</span><span class="p">(</span><span class="kc">False</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="k">def</span> <span class="nf">exclude</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a new QuerySet instance with NOT (args) ANDed to the existing</span> <span class="sd"> set.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_filter_or_exclude</span><span class="p">(</span><span class="kc">True</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_filter_or_exclude</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">negate</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="k">if</span> <span class="n">args</span> <span class="ow">or</span> <span class="n">kwargs</span><span class="p">:</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">(),</span> \ <span class="s2">"Cannot filter a query once a slice has been taken."</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="k">if</span> <span class="n">negate</span><span class="p">:</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_q</span><span class="p">(</span><span class="o">~</span><span class="n">Q</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">))</span> <span class="k">else</span><span class="p">:</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_q</span><span class="p">(</span><span class="n">Q</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">))</span> <span class="k">return</span> <span class="n">clone</span> <span class="k">def</span> <span class="nf">complex_filter</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">filter_obj</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a new QuerySet instance with filter_obj added to the filters.</span> <span class="sd"> filter_obj can be a Q object (or anything with an add_to_query()</span> <span class="sd"> method) or a dictionary of keyword lookup arguments.</span> <span class="sd"> This exists to support framework features such as 'limit_choices_to',</span> <span class="sd"> and usually it will be more natural to use other methods.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">filter_obj</span><span class="p">,</span> <span class="n">Q</span><span class="p">)</span> <span class="ow">or</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">filter_obj</span><span class="p">,</span> <span class="s1">'add_to_query'</span><span class="p">):</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_q</span><span class="p">(</span><span class="n">filter_obj</span><span class="p">)</span> <span class="k">return</span> <span class="n">clone</span> <span class="k">else</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_filter_or_exclude</span><span class="p">(</span><span class="kc">None</span><span class="p">,</span> <span class="o">**</span><span class="n">filter_obj</span><span class="p">)</span> <span class="k">def</span> <span class="nf">select_for_update</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">nowait</span><span class="o">=</span><span class="kc">False</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a new QuerySet instance that will select objects with a</span> <span class="sd"> FOR UPDATE lock.</span> <span class="sd"> """</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">obj</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">select_for_update</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">select_for_update_nowait</span> <span class="o">=</span> <span class="n">nowait</span> <span class="k">return</span> <span class="n">obj</span> <span class="k">def</span> <span class="nf">select_related</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">fields</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a new QuerySet instance that will select related objects.</span> <span class="sd"> If fields are specified, they must be ForeignKey fields and only those</span> <span class="sd"> related objects are included in the selection.</span> <span class="sd"> If select_related(None) is called, the list is cleared.</span> <span class="sd"> """</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="k">if</span> <span class="n">fields</span> <span class="o">==</span> <span class="p">(</span><span class="kc">None</span><span class="p">,):</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">select_related</span> <span class="o">=</span> <span class="kc">False</span> <span class="k">elif</span> <span class="n">fields</span><span class="p">:</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_select_related</span><span class="p">(</span><span class="n">fields</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">select_related</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">return</span> <span class="n">obj</span> <span class="k">def</span> <span class="nf">prefetch_related</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">lookups</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a new QuerySet instance that will prefetch the specified</span> <span class="sd"> Many-To-One and Many-To-Many related objects when the QuerySet is</span> <span class="sd"> evaluated.</span> <span class="sd"> When prefetch_related() is called more than once, the list of lookups to</span> <span class="sd"> prefetch is appended to. If prefetch_related(None) is called, the list</span> <span class="sd"> is cleared.</span> <span class="sd"> """</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="k">if</span> <span class="n">lookups</span> <span class="o">==</span> <span class="p">(</span><span class="kc">None</span><span class="p">,):</span> <span class="n">clone</span><span class="o">.</span><span class="n">_prefetch_related_lookups</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">else</span><span class="p">:</span> <span class="n">clone</span><span class="o">.</span><span class="n">_prefetch_related_lookups</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">lookups</span><span class="p">)</span> <span class="k">return</span> <span class="n">clone</span> <span class="k">def</span> <span class="nf">annotate</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Return a query set in which the returned objects have been annotated</span> <span class="sd"> with extra data or aggregations.</span> <span class="sd"> """</span> <span class="n">annotations</span> <span class="o">=</span> <span class="n">OrderedDict</span><span class="p">()</span> <span class="c1"># To preserve ordering of args</span> <span class="k">for</span> <span class="n">arg</span> <span class="ow">in</span> <span class="n">args</span><span class="p">:</span> <span class="c1"># The default_alias property may raise a TypeError, so we use</span> <span class="c1"># a try/except construct rather than hasattr in order to remain</span> <span class="c1"># consistent between PY2 and PY3 (hasattr would swallow</span> <span class="c1"># the TypeError on PY2).</span> <span class="k">try</span><span class="p">:</span> <span class="k">if</span> <span class="n">arg</span><span class="o">.</span><span class="n">default_alias</span> <span class="ow">in</span> <span class="n">kwargs</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"The named annotation '</span><span class="si">%s</span><span class="s2">' conflicts with the "</span> <span class="s2">"default name for another annotation."</span> <span class="o">%</span> <span class="n">arg</span><span class="o">.</span><span class="n">default_alias</span><span class="p">)</span> <span class="k">except</span> <span class="p">(</span><span class="ne">AttributeError</span><span class="p">,</span> <span class="ne">TypeError</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"Complex annotations require an alias"</span><span class="p">)</span> <span class="n">annotations</span><span class="p">[</span><span class="n">arg</span><span class="o">.</span><span class="n">default_alias</span><span class="p">]</span> <span class="o">=</span> <span class="n">arg</span> <span class="n">annotations</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">kwargs</span><span class="p">)</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">names</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="s1">'_fields'</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="k">if</span> <span class="n">names</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">names</span> <span class="o">=</span> <span class="p">{</span><span class="n">f</span><span class="o">.</span><span class="n">name</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_fields</span><span class="p">()}</span> <span class="c1"># Add the annotations to the query</span> <span class="k">for</span> <span class="n">alias</span><span class="p">,</span> <span class="n">annotation</span> <span class="ow">in</span> <span class="n">annotations</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="k">if</span> <span class="n">alias</span> <span class="ow">in</span> <span class="n">names</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"The annotation '</span><span class="si">%s</span><span class="s2">' conflicts with a field on "</span> <span class="s2">"the model."</span> <span class="o">%</span> <span class="n">alias</span><span class="p">)</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_annotation</span><span class="p">(</span><span class="n">annotation</span><span class="p">,</span> <span class="n">alias</span><span class="p">,</span> <span class="n">is_summary</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="c1"># expressions need to be added to the query before we know if they contain aggregates</span> <span class="n">added_aggregates</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">alias</span><span class="p">,</span> <span class="n">annotation</span> <span class="ow">in</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">annotations</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="k">if</span> <span class="n">alias</span> <span class="ow">in</span> <span class="n">annotations</span> <span class="ow">and</span> <span class="n">annotation</span><span class="o">.</span><span class="n">contains_aggregate</span><span class="p">:</span> <span class="n">added_aggregates</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">alias</span><span class="p">)</span> <span class="k">if</span> <span class="n">added_aggregates</span><span class="p">:</span> <span class="n">obj</span><span class="o">.</span><span class="n">_setup_aggregate_query</span><span class="p">(</span><span class="nb">list</span><span class="p">(</span><span class="n">added_aggregates</span><span class="p">))</span> <span class="k">return</span> <span class="n">obj</span> <span class="k">def</span> <span class="nf">order_by</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">field_names</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a new QuerySet instance with the ordering changed.</span> <span class="sd"> """</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">(),</span> \ <span class="s2">"Cannot reorder a query once a slice has been taken."</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clear_ordering</span><span class="p">(</span><span class="n">force_empty</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_ordering</span><span class="p">(</span><span class="o">*</span><span class="n">field_names</span><span class="p">)</span> <span class="k">return</span> <span class="n">obj</span> <span class="k">def</span> <span class="nf">distinct</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">field_names</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns a new QuerySet instance that will select only distinct results.</span> <span class="sd"> """</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">(),</span> \ <span class="s2">"Cannot create distinct fields once a slice has been taken."</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_distinct_fields</span><span class="p">(</span><span class="o">*</span><span class="n">field_names</span><span class="p">)</span> <span class="k">return</span> <span class="n">obj</span> <span class="k">def</span> <span class="nf">extra</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">select</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">where</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">params</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">tables</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">order_by</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">select_params</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Adds extra SQL fragments to the query.</span> <span class="sd"> """</span> <span class="k">assert</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">can_filter</span><span class="p">(),</span> \ <span class="s2">"Cannot change a query once a slice has been taken"</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_extra</span><span class="p">(</span><span class="n">select</span><span class="p">,</span> <span class="n">select_params</span><span class="p">,</span> <span class="n">where</span><span class="p">,</span> <span class="n">params</span><span class="p">,</span> <span class="n">tables</span><span class="p">,</span> <span class="n">order_by</span><span class="p">)</span> <span class="k">return</span> <span class="n">clone</span> <span class="k">def</span> <span class="nf">reverse</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Reverses the ordering of the QuerySet.</span> <span class="sd"> """</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">standard_ordering</span> <span class="o">=</span> <span class="ow">not</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">standard_ordering</span> <span class="k">return</span> <span class="n">clone</span> <span class="k">def</span> <span class="nf">defer</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">fields</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Defers the loading of data for certain fields until they are accessed.</span> <span class="sd"> The set of fields to defer is added to any existing set of deferred</span> <span class="sd"> fields. The only exception to this is if None is passed in as the only</span> <span class="sd"> parameter, in which case all deferrals are removed (None acts as a</span> <span class="sd"> reset option).</span> <span class="sd"> """</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="k">if</span> <span class="n">fields</span> <span class="o">==</span> <span class="p">(</span><span class="kc">None</span><span class="p">,):</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clear_deferred_loading</span><span class="p">()</span> <span class="k">else</span><span class="p">:</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_deferred_loading</span><span class="p">(</span><span class="n">fields</span><span class="p">)</span> <span class="k">return</span> <span class="n">clone</span> <span class="k">def</span> <span class="nf">only</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">fields</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Essentially, the opposite of defer. Only the fields passed into this</span> <span class="sd"> method and that are not already specified as deferred are loaded</span> <span class="sd"> immediately when the queryset is evaluated.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="n">fields</span> <span class="o">==</span> <span class="p">(</span><span class="kc">None</span><span class="p">,):</span> <span class="c1"># Can only pass None to defer(), not only(), as the rest option.</span> <span class="c1"># That won't stop people trying to do this, so let's be explicit.</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"Cannot pass None as an argument to only()."</span><span class="p">)</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">clone</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_immediate_loading</span><span class="p">(</span><span class="n">fields</span><span class="p">)</span> <span class="k">return</span> <span class="n">clone</span> <span class="k">def</span> <span class="nf">using</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">alias</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Selects which database this QuerySet should execute its query against.</span> <span class="sd"> """</span> <span class="n">clone</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="n">clone</span><span class="o">.</span><span class="n">_db</span> <span class="o">=</span> <span class="n">alias</span> <span class="k">return</span> <span class="n">clone</span> <span class="c1">###################################</span> <span class="c1"># PUBLIC INTROSPECTION ATTRIBUTES #</span> <span class="c1">###################################</span> <span class="k">def</span> <span class="nf">ordered</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns True if the QuerySet is ordered -- i.e. has an order_by()</span> <span class="sd"> clause or a default ordering on the model.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">extra_order_by</span> <span class="ow">or</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">order_by</span><span class="p">:</span> <span class="k">return</span> <span class="kc">True</span> <span class="k">elif</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">default_ordering</span> <span class="ow">and</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">get_meta</span><span class="p">()</span><span class="o">.</span><span class="n">ordering</span><span class="p">:</span> <span class="k">return</span> <span class="kc">True</span> <span class="k">else</span><span class="p">:</span> <span class="k">return</span> <span class="kc">False</span> <span class="n">ordered</span> <span class="o">=</span> <span class="nb">property</span><span class="p">(</span><span class="n">ordered</span><span class="p">)</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">db</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="s2">"Return the database that will be used if this query is executed now"</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_for_write</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_db</span> <span class="ow">or</span> <span class="n">router</span><span class="o">.</span><span class="n">db_for_write</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">_hints</span><span class="p">)</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_db</span> <span class="ow">or</span> <span class="n">router</span><span class="o">.</span><span class="n">db_for_read</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">_hints</span><span class="p">)</span> <span class="c1">###################</span> <span class="c1"># PRIVATE METHODS #</span> <span class="c1">###################</span> <span class="k">def</span> <span class="nf">_insert</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">objs</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="n">return_id</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">raw</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Inserts a new record for the given model. This provides an interface to</span> <span class="sd"> the InsertQuery class and is how Model.save() is implemented.</span> <span class="sd"> """</span> <span class="bp">self</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">if</span> <span class="n">using</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">using</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">db</span> <span class="n">query</span> <span class="o">=</span> <span class="n">sql</span><span class="o">.</span><span class="n">InsertQuery</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">)</span> <span class="n">query</span><span class="o">.</span><span class="n">insert_values</span><span class="p">(</span><span class="n">fields</span><span class="p">,</span> <span class="n">objs</span><span class="p">,</span> <span class="n">raw</span><span class="o">=</span><span class="n">raw</span><span class="p">)</span> <span class="k">return</span> <span class="n">query</span><span class="o">.</span><span class="n">get_compiler</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="n">using</span><span class="p">)</span><span class="o">.</span><span class="n">execute_sql</span><span class="p">(</span><span class="n">return_id</span><span class="p">)</span> <span class="n">_insert</span><span class="o">.</span><span class="n">alters_data</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">_insert</span><span class="o">.</span><span class="n">queryset_only</span> <span class="o">=</span> <span class="kc">False</span> <span class="k">def</span> <span class="nf">_batched_insert</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">objs</span><span class="p">,</span> <span class="n">fields</span><span class="p">,</span> <span class="n">batch_size</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> A little helper method for bulk_insert to insert the bulk one batch</span> <span class="sd"> at a time. Inserts recursively a batch from the front of the bulk and</span> <span class="sd"> then _batched_insert() the remaining objects again.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">objs</span><span class="p">:</span> <span class="k">return</span> <span class="n">ops</span> <span class="o">=</span> <span class="n">connections</span><span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">]</span><span class="o">.</span><span class="n">ops</span> <span class="n">batch_size</span> <span class="o">=</span> <span class="p">(</span><span class="n">batch_size</span> <span class="ow">or</span> <span class="nb">max</span><span class="p">(</span><span class="n">ops</span><span class="o">.</span><span class="n">bulk_batch_size</span><span class="p">(</span><span class="n">fields</span><span class="p">,</span> <span class="n">objs</span><span class="p">),</span> <span class="mi">1</span><span class="p">))</span> <span class="k">for</span> <span class="n">batch</span> <span class="ow">in</span> <span class="p">[</span><span class="n">objs</span><span class="p">[</span><span class="n">i</span><span class="p">:</span><span class="n">i</span> <span class="o">+</span> <span class="n">batch_size</span><span class="p">]</span> <span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="nb">len</span><span class="p">(</span><span class="n">objs</span><span class="p">),</span> <span class="n">batch_size</span><span class="p">)]:</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_base_manager</span><span class="o">.</span><span class="n">_insert</span><span class="p">(</span><span class="n">batch</span><span class="p">,</span> <span class="n">fields</span><span class="o">=</span><span class="n">fields</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_clone</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">klass</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">setup</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="n">base_queryset_class</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="s1">'_base_queryset_class'</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">)</span> <span class="k">if</span> <span class="n">klass</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">klass</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span> <span class="k">elif</span> <span class="ow">not</span> <span class="p">(</span><span class="nb">issubclass</span><span class="p">(</span><span class="n">base_queryset_class</span><span class="p">,</span> <span class="n">klass</span><span class="p">)</span> <span class="ow">or</span> <span class="nb">issubclass</span><span class="p">(</span><span class="n">klass</span><span class="p">,</span> <span class="n">base_queryset_class</span><span class="p">)):</span> <span class="n">class_bases</span> <span class="o">=</span> <span class="p">(</span><span class="n">klass</span><span class="p">,</span> <span class="n">base_queryset_class</span><span class="p">)</span> <span class="n">class_dict</span> <span class="o">=</span> <span class="p">{</span> <span class="s1">'_base_queryset_class'</span><span class="p">:</span> <span class="n">base_queryset_class</span><span class="p">,</span> <span class="s1">'_specialized_queryset_class'</span><span class="p">:</span> <span class="n">klass</span><span class="p">,</span> <span class="p">}</span> <span class="n">klass</span> <span class="o">=</span> <span class="nb">type</span><span class="p">(</span><span class="n">klass</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="n">class_bases</span><span class="p">,</span> <span class="n">class_dict</span><span class="p">)</span> <span class="n">query</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clone</span><span class="p">()</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_sticky_filter</span><span class="p">:</span> <span class="n">query</span><span class="o">.</span><span class="n">filter_is_sticky</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">c</span> <span class="o">=</span> <span class="n">klass</span><span class="p">(</span><span class="n">model</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">,</span> <span class="n">query</span><span class="o">=</span><span class="n">query</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">_db</span><span class="p">,</span> <span class="n">hints</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">_hints</span><span class="p">)</span> <span class="n">c</span><span class="o">.</span><span class="n">_for_write</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_for_write</span> <span class="n">c</span><span class="o">.</span><span class="n">_prefetch_related_lookups</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_prefetch_related_lookups</span><span class="p">[:]</span> <span class="n">c</span><span class="o">.</span><span class="n">_known_related_objects</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_known_related_objects</span> <span class="n">c</span><span class="o">.</span><span class="n">__dict__</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">kwargs</span><span class="p">)</span> <span class="k">if</span> <span class="n">setup</span> <span class="ow">and</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">c</span><span class="p">,</span> <span class="s1">'_setup_query'</span><span class="p">):</span> <span class="n">c</span><span class="o">.</span><span class="n">_setup_query</span><span class="p">()</span> <span class="k">return</span> <span class="n">c</span> <span class="k">def</span> <span class="nf">_fetch_all</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">_result_cache</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">iterator</span><span class="p">())</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_prefetch_related_lookups</span> <span class="ow">and</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_prefetch_done</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">_prefetch_related_objects</span><span class="p">()</span> <span class="k">def</span> <span class="nf">_next_is_sticky</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Indicates that the next filter call and the one following that should</span> <span class="sd"> be treated as a single filter. This is only important when it comes to</span> <span class="sd"> determining when to reuse tables for many-to-many filters. Required so</span> <span class="sd"> that we can filter naturally on the results of related managers.</span> <span class="sd"> This doesn't return a clone of the current QuerySet (it returns</span> <span class="sd"> "self"). The method is only used internally and should be immediately</span> <span class="sd"> followed by a filter() that does create a clone.</span> <span class="sd"> """</span> <span class="bp">self</span><span class="o">.</span><span class="n">_sticky_filter</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">return</span> <span class="bp">self</span> <span class="k">def</span> <span class="nf">_merge_sanity_check</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Checks that we are merging two comparable QuerySet classes. By default</span> <span class="sd"> this does nothing, but see the ValuesQuerySet for an example of where</span> <span class="sd"> it's useful.</span> <span class="sd"> """</span> <span class="k">pass</span> <span class="k">def</span> <span class="nf">_merge_known_related_objects</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Keep track of all known related objects from either QuerySet instance.</span> <span class="sd"> """</span> <span class="k">for</span> <span class="n">field</span><span class="p">,</span> <span class="n">objects</span> <span class="ow">in</span> <span class="n">other</span><span class="o">.</span><span class="n">_known_related_objects</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="bp">self</span><span class="o">.</span><span class="n">_known_related_objects</span><span class="o">.</span><span class="n">setdefault</span><span class="p">(</span><span class="n">field</span><span class="p">,</span> <span class="p">{})</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">objects</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_setup_aggregate_query</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">aggregates</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Prepare the query for computing a result that contains aggregate annotations.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">group_by</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">group_by</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">def</span> <span class="nf">_prepare</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span> <span class="k">def</span> <span class="nf">_as_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">connection</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Returns the internal query's SQL and parameters (as a tuple).</span> <span class="sd"> """</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">values</span><span class="p">(</span><span class="s2">"pk"</span><span class="p">)</span> <span class="k">if</span> <span class="n">obj</span><span class="o">.</span><span class="n">_db</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">or</span> <span class="n">connection</span> <span class="o">==</span> <span class="n">connections</span><span class="p">[</span><span class="n">obj</span><span class="o">.</span><span class="n">_db</span><span class="p">]:</span> <span class="k">return</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">get_compiler</span><span class="p">(</span><span class="n">connection</span><span class="o">=</span><span class="n">connection</span><span class="p">)</span><span class="o">.</span><span class="n">as_nested_sql</span><span class="p">()</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"Can't do subqueries with queries on different DBs."</span><span class="p">)</span> <span class="c1"># When used as part of a nested query, a queryset will never be an "always</span> <span class="c1"># empty" result.</span> <span class="n">value_annotation</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">def</span> <span class="nf">_add_hints</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">**</span><span class="n">hints</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Update hinting information for later use by Routers</span> <span class="sd"> """</span> <span class="c1"># If there is any hinting information, add it to what we already know.</span> <span class="c1"># If we have a new hint for an existing key, overwrite with the new value.</span> <span class="bp">self</span><span class="o">.</span><span class="n">_hints</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">hints</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_has_filters</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Checks if this QuerySet has any filtering going on. Note that this</span> <span class="sd"> isn't equivalent for checking if all objects are present in results,</span> <span class="sd"> for example qs[1:]._has_filters() -> False.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">has_filters</span><span class="p">()</span> <span class="k">def</span> <span class="nf">is_compatible_query_object_type</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">opts</span><span class="p">):</span> <span class="n">model</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span> <span class="k">return</span> <span class="p">(</span> <span class="n">model</span> <span class="o">==</span> <span class="n">opts</span><span class="o">.</span><span class="n">concrete_model</span> <span class="ow">or</span> <span class="n">opts</span><span class="o">.</span><span class="n">concrete_model</span> <span class="ow">in</span> <span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_parent_list</span><span class="p">()</span> <span class="ow">or</span> <span class="n">model</span> <span class="ow">in</span> <span class="n">opts</span><span class="o">.</span><span class="n">get_parent_list</span><span class="p">()</span> <span class="p">)</span> <span class="n">is_compatible_query_object_type</span><span class="o">.</span><span class="n">queryset_only</span> <span class="o">=</span> <span class="kc">True</span></div> <span class="k">class</span> <span class="nc">InstanceCheckMeta</span><span class="p">(</span><span class="nb">type</span><span class="p">):</span> <span class="k">def</span> <span class="nf">__instancecheck__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">instance</span><span class="p">):</span> <span class="k">return</span> <span class="n">instance</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">is_empty</span><span class="p">()</span> <span class="k">class</span> <span class="nc">EmptyQuerySet</span><span class="p">(</span><span class="n">six</span><span class="o">.</span><span class="n">with_metaclass</span><span class="p">(</span><span class="n">InstanceCheckMeta</span><span class="p">)):</span> <span class="sd">"""</span> <span class="sd"> Marker class usable for checking if a queryset is empty by .none():</span> <span class="sd"> isinstance(qs.none(), EmptyQuerySet) -> True</span> <span class="sd"> """</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"EmptyQuerySet can't be instantiated"</span><span class="p">)</span> <span class="k">class</span> <span class="nc">ValuesQuerySet</span><span class="p">(</span><span class="n">QuerySet</span><span class="p">):</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="nb">super</span><span class="p">(</span><span class="n">ValuesQuerySet</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">__init__</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="c1"># select_related isn't supported in values(). (FIXME -#3358)</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">select_related</span> <span class="o">=</span> <span class="kc">False</span> <span class="c1"># QuerySet.clone() will also set up the _fields attribute with the</span> <span class="c1"># names of the model fields to select.</span> <span class="k">def</span> <span class="nf">only</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">fields</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">NotImplementedError</span><span class="p">(</span><span class="s2">"ValuesQuerySet does not implement only()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">defer</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">fields</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">NotImplementedError</span><span class="p">(</span><span class="s2">"ValuesQuerySet does not implement defer()"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">iterator</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="c1"># Purge any extra columns that haven't been explicitly asked for</span> <span class="n">extra_names</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">extra_select</span><span class="p">)</span> <span class="n">field_names</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">field_names</span> <span class="n">annotation_names</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">annotation_select</span><span class="p">)</span> <span class="n">names</span> <span class="o">=</span> <span class="n">extra_names</span> <span class="o">+</span> <span class="n">field_names</span> <span class="o">+</span> <span class="n">annotation_names</span> <span class="k">for</span> <span class="n">row</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">get_compiler</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span><span class="o">.</span><span class="n">results_iter</span><span class="p">():</span> <span class="k">yield</span> <span class="nb">dict</span><span class="p">(</span><span class="nb">zip</span><span class="p">(</span><span class="n">names</span><span class="p">,</span> <span class="n">row</span><span class="p">))</span> <span class="k">def</span> <span class="nf">delete</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="c1"># values().delete() doesn't work currently - make sure it raises an</span> <span class="c1"># user friendly error.</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"Queries with .values() or .values_list() applied "</span> <span class="s2">"can't be deleted"</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_setup_query</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Constructs the field_names list that the values query will be</span> <span class="sd"> retrieving.</span> <span class="sd"> Called by the _clone() method after initializing the rest of the</span> <span class="sd"> instance.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">group_by</span> <span class="ow">is</span> <span class="kc">True</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_fields</span><span class="p">([</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">],</span> <span class="kc">False</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">set_group_by</span><span class="p">()</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clear_deferred_loading</span><span class="p">()</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clear_select_fields</span><span class="p">()</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">extra_names</span> <span class="o">=</span> <span class="p">[]</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">if</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">_extra</span> <span class="ow">and</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">_annotations</span><span class="p">:</span> <span class="c1"># Short cut - if there are no extra or annotations, then</span> <span class="c1"># the values() clause must be just field names.</span> <span class="bp">self</span><span class="o">.</span><span class="n">field_names</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">default_cols</span> <span class="o">=</span> <span class="kc">False</span> <span class="bp">self</span><span class="o">.</span><span class="n">field_names</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">:</span> <span class="c1"># we inspect the full extra_select list since we might</span> <span class="c1"># be adding back an extra select item that we hadn't</span> <span class="c1"># had selected previously.</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">_extra</span> <span class="ow">and</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">_extra</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">extra_names</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="k">elif</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">annotation_select</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">field_names</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">f</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># Default to all fields.</span> <span class="bp">self</span><span class="o">.</span><span class="n">extra_names</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">field_names</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">]</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span> <span class="o">=</span> <span class="kc">None</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">select</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">extra_names</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">set_extra_mask</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">extra_names</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">add_fields</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">field_names</span><span class="p">,</span> <span class="kc">True</span><span class="p">)</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">set_annotation_mask</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_clone</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">klass</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">setup</span><span class="o">=</span><span class="kc">False</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Cloning a ValuesQuerySet preserves the current fields.</span> <span class="sd"> """</span> <span class="n">c</span> <span class="o">=</span> <span class="nb">super</span><span class="p">(</span><span class="n">ValuesQuerySet</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">_clone</span><span class="p">(</span><span class="n">klass</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">c</span><span class="p">,</span> <span class="s1">'_fields'</span><span class="p">):</span> <span class="c1"># Only clone self._fields if _fields wasn't passed into the cloning</span> <span class="c1"># call directly.</span> <span class="n">c</span><span class="o">.</span><span class="n">_fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">[:]</span> <span class="n">c</span><span class="o">.</span><span class="n">field_names</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">field_names</span> <span class="n">c</span><span class="o">.</span><span class="n">extra_names</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">extra_names</span> <span class="n">c</span><span class="o">.</span><span class="n">annotation_names</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span> <span class="k">if</span> <span class="n">setup</span> <span class="ow">and</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">c</span><span class="p">,</span> <span class="s1">'_setup_query'</span><span class="p">):</span> <span class="n">c</span><span class="o">.</span><span class="n">_setup_query</span><span class="p">()</span> <span class="k">return</span> <span class="n">c</span> <span class="k">def</span> <span class="nf">_merge_sanity_check</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span> <span class="nb">super</span><span class="p">(</span><span class="n">ValuesQuerySet</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">_merge_sanity_check</span><span class="p">(</span><span class="n">other</span><span class="p">)</span> <span class="k">if</span> <span class="p">(</span><span class="nb">set</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">extra_names</span><span class="p">)</span> <span class="o">!=</span> <span class="nb">set</span><span class="p">(</span><span class="n">other</span><span class="o">.</span><span class="n">extra_names</span><span class="p">)</span> <span class="ow">or</span> <span class="nb">set</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">field_names</span><span class="p">)</span> <span class="o">!=</span> <span class="nb">set</span><span class="p">(</span><span class="n">other</span><span class="o">.</span><span class="n">field_names</span><span class="p">)</span> <span class="ow">or</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span> <span class="o">!=</span> <span class="n">other</span><span class="o">.</span><span class="n">annotation_names</span><span class="p">):</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s2">"Merging '</span><span class="si">%s</span><span class="s2">' classes must involve the same values in each case."</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__name__</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_setup_aggregate_query</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">aggregates</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Prepare the query for computing a result that contains aggregate annotations.</span> <span class="sd"> """</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">set_group_by</span><span class="p">()</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">aggregates</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">set_annotation_mask</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">annotation_names</span><span class="p">)</span> <span class="nb">super</span><span class="p">(</span><span class="n">ValuesQuerySet</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">_setup_aggregate_query</span><span class="p">(</span><span class="n">aggregates</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_as_sql</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">connection</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> For ValuesQuerySet (and subclasses like ValuesListQuerySet), they can</span> <span class="sd"> only be used as nested queries if they're already set up to select only</span> <span class="sd"> a single field (in which case, that is the field column that is</span> <span class="sd"> returned). This differs from QuerySet.as_sql(), where the column to</span> <span class="sd"> select is set up by Django.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="p">((</span><span class="bp">self</span><span class="o">.</span><span class="n">_fields</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">)</span> <span class="o">></span> <span class="mi">1</span><span class="p">)</span> <span class="ow">or</span> <span class="p">(</span><span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fields</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">)</span> <span class="o">></span> <span class="mi">1</span><span class="p">)):</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s1">'Cannot use a multi-field </span><span class="si">%s</span><span class="s1"> as a filter value.'</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__name__</span><span class="p">)</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_clone</span><span class="p">()</span> <span class="k">if</span> <span class="n">obj</span><span class="o">.</span><span class="n">_db</span> <span class="ow">is</span> <span class="kc">None</span> <span class="ow">or</span> <span class="n">connection</span> <span class="o">==</span> <span class="n">connections</span><span class="p">[</span><span class="n">obj</span><span class="o">.</span><span class="n">_db</span><span class="p">]:</span> <span class="k">return</span> <span class="n">obj</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">get_compiler</span><span class="p">(</span><span class="n">connection</span><span class="o">=</span><span class="n">connection</span><span class="p">)</span><span class="o">.</span><span class="n">as_nested_sql</span><span class="p">()</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"Can't do subqueries with queries on different DBs."</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_prepare</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Validates that we aren't trying to do a query like</span> <span class="sd"> value__in=qs.values('value1', 'value2'), which isn't valid.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="p">((</span><span class="bp">self</span><span class="o">.</span><span class="n">_fields</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">)</span> <span class="o">></span> <span class="mi">1</span><span class="p">)</span> <span class="ow">or</span> <span class="p">(</span><span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fields</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">)</span> <span class="o">></span> <span class="mi">1</span><span class="p">)):</span> <span class="k">raise</span> <span class="ne">TypeError</span><span class="p">(</span><span class="s1">'Cannot use a multi-field </span><span class="si">%s</span><span class="s1"> as a filter value.'</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__name__</span><span class="p">)</span> <span class="k">return</span> <span class="bp">self</span> <span class="k">def</span> <span class="nf">is_compatible_query_object_type</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">opts</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> ValueQuerySets do not need to be checked for compatibility.</span> <span class="sd"> We trust that users of ValueQuerySets know what they are doing.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="kc">True</span> <span class="k">class</span> <span class="nc">ValuesListQuerySet</span><span class="p">(</span><span class="n">ValuesQuerySet</span><span class="p">):</span> <span class="k">def</span> <span class="nf">iterator</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="n">compiler</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">get_compiler</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">flat</span> <span class="ow">and</span> <span class="nb">len</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">)</span> <span class="o">==</span> <span class="mi">1</span><span class="p">:</span> <span class="k">for</span> <span class="n">row</span> <span class="ow">in</span> <span class="n">compiler</span><span class="o">.</span><span class="n">results_iter</span><span class="p">():</span> <span class="k">yield</span> <span class="n">row</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">elif</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">extra_select</span> <span class="ow">and</span> <span class="ow">not</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">annotation_select</span><span class="p">:</span> <span class="k">for</span> <span class="n">row</span> <span class="ow">in</span> <span class="n">compiler</span><span class="o">.</span><span class="n">results_iter</span><span class="p">():</span> <span class="k">yield</span> <span class="nb">tuple</span><span class="p">(</span><span class="n">row</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># When extra(select=...) or an annotation is involved, the extra</span> <span class="c1"># cols are always at the start of the row, and we need to reorder</span> <span class="c1"># the fields to match the order in self._fields.</span> <span class="n">extra_names</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">extra_select</span><span class="p">)</span> <span class="n">field_names</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">field_names</span> <span class="n">annotation_names</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">annotation_select</span><span class="p">)</span> <span class="n">names</span> <span class="o">=</span> <span class="n">extra_names</span> <span class="o">+</span> <span class="n">field_names</span> <span class="o">+</span> <span class="n">annotation_names</span> <span class="c1"># If a field list has been specified, use it. Otherwise, use the</span> <span class="c1"># full list of fields, including extras and annotations.</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">:</span> <span class="n">fields</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">)</span> <span class="o">+</span> <span class="p">[</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">annotation_names</span> <span class="k">if</span> <span class="n">f</span> <span class="ow">not</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">_fields</span><span class="p">]</span> <span class="k">else</span><span class="p">:</span> <span class="n">fields</span> <span class="o">=</span> <span class="n">names</span> <span class="k">for</span> <span class="n">row</span> <span class="ow">in</span> <span class="n">compiler</span><span class="o">.</span><span class="n">results_iter</span><span class="p">():</span> <span class="n">data</span> <span class="o">=</span> <span class="nb">dict</span><span class="p">(</span><span class="nb">zip</span><span class="p">(</span><span class="n">names</span><span class="p">,</span> <span class="n">row</span><span class="p">))</span> <span class="k">yield</span> <span class="nb">tuple</span><span class="p">(</span><span class="n">data</span><span class="p">[</span><span class="n">f</span><span class="p">]</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span><span class="p">)</span> <span class="k">def</span> <span class="nf">_clone</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span> <span class="n">clone</span> <span class="o">=</span> <span class="nb">super</span><span class="p">(</span><span class="n">ValuesListQuerySet</span><span class="p">,</span> <span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="n">_clone</span><span class="p">(</span><span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">clone</span><span class="p">,</span> <span class="s2">"flat"</span><span class="p">):</span> <span class="c1"># Only assign flat if the clone didn't already get it from kwargs</span> <span class="n">clone</span><span class="o">.</span><span class="n">flat</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">flat</span> <span class="k">return</span> <span class="n">clone</span> <span class="k">class</span> <span class="nc">RawQuerySet</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Provides an iterator which converts the results of raw SQL queries into</span> <span class="sd"> annotated model instances.</span> <span class="sd"> """</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">raw_query</span><span class="p">,</span> <span class="n">model</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">query</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">params</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">translations</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">hints</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">raw_query</span> <span class="o">=</span> <span class="n">raw_query</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span> <span class="o">=</span> <span class="n">model</span> <span class="bp">self</span><span class="o">.</span><span class="n">_db</span> <span class="o">=</span> <span class="n">using</span> <span class="bp">self</span><span class="o">.</span><span class="n">_hints</span> <span class="o">=</span> <span class="n">hints</span> <span class="ow">or</span> <span class="p">{}</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span> <span class="o">=</span> <span class="n">query</span> <span class="ow">or</span> <span class="n">sql</span><span class="o">.</span><span class="n">RawQuery</span><span class="p">(</span><span class="n">sql</span><span class="o">=</span><span class="n">raw_query</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">,</span> <span class="n">params</span><span class="o">=</span><span class="n">params</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">params</span> <span class="o">=</span> <span class="n">params</span> <span class="ow">or</span> <span class="p">()</span> <span class="bp">self</span><span class="o">.</span><span class="n">translations</span> <span class="o">=</span> <span class="n">translations</span> <span class="ow">or</span> <span class="p">{}</span> <span class="k">def</span> <span class="nf">resolve_model_init_order</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Resolve the init field names and value positions</span> <span class="sd"> """</span> <span class="n">model_init_fields</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">column</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">columns</span><span class="p">]</span> <span class="n">annotation_fields</span> <span class="o">=</span> <span class="p">[(</span><span class="n">column</span><span class="p">,</span> <span class="n">pos</span><span class="p">)</span> <span class="k">for</span> <span class="n">pos</span><span class="p">,</span> <span class="n">column</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">columns</span><span class="p">)</span> <span class="k">if</span> <span class="n">column</span> <span class="ow">not</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">model_fields</span><span class="p">]</span> <span class="n">model_init_order</span> <span class="o">=</span> <span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">columns</span><span class="o">.</span><span class="n">index</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">column</span><span class="p">)</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">model_init_fields</span><span class="p">]</span> <span class="n">model_init_names</span> <span class="o">=</span> <span class="p">[</span><span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">model_init_fields</span><span class="p">]</span> <span class="k">return</span> <span class="n">model_init_names</span><span class="p">,</span> <span class="n">model_init_order</span><span class="p">,</span> <span class="n">annotation_fields</span> <span class="k">def</span> <span class="nf">__iter__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="c1"># Cache some things for performance reasons outside the loop.</span> <span class="n">db</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">db</span> <span class="n">compiler</span> <span class="o">=</span> <span class="n">connections</span><span class="p">[</span><span class="n">db</span><span class="p">]</span><span class="o">.</span><span class="n">ops</span><span class="o">.</span><span class="n">compiler</span><span class="p">(</span><span class="s1">'SQLCompiler'</span><span class="p">)(</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="p">,</span> <span class="n">connections</span><span class="p">[</span><span class="n">db</span><span class="p">],</span> <span class="n">db</span> <span class="p">)</span> <span class="n">query</span> <span class="o">=</span> <span class="nb">iter</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="p">)</span> <span class="k">try</span><span class="p">:</span> <span class="n">model_init_names</span><span class="p">,</span> <span class="n">model_init_pos</span><span class="p">,</span> <span class="n">annotation_fields</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">resolve_model_init_order</span><span class="p">()</span> <span class="c1"># Find out which model's fields are not present in the query.</span> <span class="n">skip</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">:</span> <span class="k">if</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">model_init_names</span><span class="p">:</span> <span class="n">skip</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="k">if</span> <span class="n">skip</span><span class="p">:</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">attname</span> <span class="ow">in</span> <span class="n">skip</span><span class="p">:</span> <span class="k">raise</span> <span class="n">InvalidQuery</span><span class="p">(</span><span class="s1">'Raw query must include the primary key'</span><span class="p">)</span> <span class="n">model_cls</span> <span class="o">=</span> <span class="n">deferred_class_factory</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">,</span> <span class="n">skip</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">model_cls</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span> <span class="n">fields</span> <span class="o">=</span> <span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">model_fields</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">c</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="k">for</span> <span class="n">c</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">columns</span><span class="p">]</span> <span class="n">converters</span> <span class="o">=</span> <span class="n">compiler</span><span class="o">.</span><span class="n">get_converters</span><span class="p">([</span> <span class="n">f</span><span class="o">.</span><span class="n">get_col</span><span class="p">(</span><span class="n">f</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">db_table</span><span class="p">)</span> <span class="k">if</span> <span class="n">f</span> <span class="k">else</span> <span class="kc">None</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">fields</span> <span class="p">])</span> <span class="k">for</span> <span class="n">values</span> <span class="ow">in</span> <span class="n">query</span><span class="p">:</span> <span class="k">if</span> <span class="n">converters</span><span class="p">:</span> <span class="n">values</span> <span class="o">=</span> <span class="n">compiler</span><span class="o">.</span><span class="n">apply_converters</span><span class="p">(</span><span class="n">values</span><span class="p">,</span> <span class="n">converters</span><span class="p">)</span> <span class="c1"># Associate fields to values</span> <span class="n">model_init_values</span> <span class="o">=</span> <span class="p">[</span><span class="n">values</span><span class="p">[</span><span class="n">pos</span><span class="p">]</span> <span class="k">for</span> <span class="n">pos</span> <span class="ow">in</span> <span class="n">model_init_pos</span><span class="p">]</span> <span class="n">instance</span> <span class="o">=</span> <span class="n">model_cls</span><span class="o">.</span><span class="n">from_db</span><span class="p">(</span><span class="n">db</span><span class="p">,</span> <span class="n">model_init_names</span><span class="p">,</span> <span class="n">model_init_values</span><span class="p">)</span> <span class="k">if</span> <span class="n">annotation_fields</span><span class="p">:</span> <span class="k">for</span> <span class="n">column</span><span class="p">,</span> <span class="n">pos</span> <span class="ow">in</span> <span class="n">annotation_fields</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">column</span><span class="p">,</span> <span class="n">values</span><span class="p">[</span><span class="n">pos</span><span class="p">])</span> <span class="k">yield</span> <span class="n">instance</span> <span class="k">finally</span><span class="p">:</span> <span class="c1"># Done iterating the Query. If it has its own cursor, close it.</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="p">,</span> <span class="s1">'cursor'</span><span class="p">)</span> <span class="ow">and</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">cursor</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">cursor</span><span class="o">.</span><span class="n">close</span><span class="p">()</span> <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="s2">"<RawQuerySet: </span><span class="si">%s</span><span class="s2">>"</span> <span class="o">%</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span> <span class="k">def</span> <span class="nf">__getitem__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">k</span><span class="p">):</span> <span class="k">return</span> <span class="nb">list</span><span class="p">(</span><span class="bp">self</span><span class="p">)[</span><span class="n">k</span><span class="p">]</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">db</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="s2">"Return the database that will be used if this query is executed now"</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_db</span> <span class="ow">or</span> <span class="n">router</span><span class="o">.</span><span class="n">db_for_read</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">,</span> <span class="o">**</span><span class="bp">self</span><span class="o">.</span><span class="n">_hints</span><span class="p">)</span> <span class="k">def</span> <span class="nf">using</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">alias</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Selects which database this Raw QuerySet should execute its query against.</span> <span class="sd"> """</span> <span class="k">return</span> <span class="n">RawQuerySet</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">raw_query</span><span class="p">,</span> <span class="n">model</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="p">,</span> <span class="n">query</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">clone</span><span class="p">(</span><span class="n">using</span><span class="o">=</span><span class="n">alias</span><span class="p">),</span> <span class="n">params</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">params</span><span class="p">,</span> <span class="n">translations</span><span class="o">=</span><span class="bp">self</span><span class="o">.</span><span class="n">translations</span><span class="p">,</span> <span class="n">using</span><span class="o">=</span><span class="n">alias</span><span class="p">)</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">columns</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> A list of model field names in the order they'll appear in the</span> <span class="sd"> query results.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="s1">'_columns'</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">_columns</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">query</span><span class="o">.</span><span class="n">get_columns</span><span class="p">()</span> <span class="c1"># Adjust any column names which don't match field names</span> <span class="k">for</span> <span class="p">(</span><span class="n">query_name</span><span class="p">,</span> <span class="n">model_name</span><span class="p">)</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">translations</span><span class="o">.</span><span class="n">items</span><span class="p">():</span> <span class="k">try</span><span class="p">:</span> <span class="n">index</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_columns</span><span class="o">.</span><span class="n">index</span><span class="p">(</span><span class="n">query_name</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">_columns</span><span class="p">[</span><span class="n">index</span><span class="p">]</span> <span class="o">=</span> <span class="n">model_name</span> <span class="k">except</span> <span class="ne">ValueError</span><span class="p">:</span> <span class="c1"># Ignore translations for non-existent column names</span> <span class="k">pass</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_columns</span> <span class="nd">@property</span> <span class="k">def</span> <span class="nf">model_fields</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> A dict mapping column names to model field names.</span> <span class="sd"> """</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="s1">'_model_fields'</span><span class="p">):</span> <span class="n">converter</span> <span class="o">=</span> <span class="n">connections</span><span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">]</span><span class="o">.</span><span class="n">introspection</span><span class="o">.</span><span class="n">table_name_converter</span> <span class="bp">self</span><span class="o">.</span><span class="n">_model_fields</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">for</span> <span class="n">field</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">fields</span><span class="p">:</span> <span class="n">name</span><span class="p">,</span> <span class="n">column</span> <span class="o">=</span> <span class="n">field</span><span class="o">.</span><span class="n">get_attname_column</span><span class="p">()</span> <span class="bp">self</span><span class="o">.</span><span class="n">_model_fields</span><span class="p">[</span><span class="n">converter</span><span class="p">(</span><span class="n">column</span><span class="p">)]</span> <span class="o">=</span> <span class="n">field</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_model_fields</span> <div class="viewcode-block" id="Prefetch"><a class="viewcode-back" href="../../../../ref/models/querysets.html#django.db.models.query.Prefetch">[docs]</a><span class="k">class</span> <span class="nc">Prefetch</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">lookup</span><span class="p">,</span> <span class="n">queryset</span><span class="o">=</span><span class="kc">None</span><span class="p">,</span> <span class="n">to_attr</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="c1"># `prefetch_through` is the path we traverse to perform the prefetch.</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_through</span> <span class="o">=</span> <span class="n">lookup</span> <span class="c1"># `prefetch_to` is the path to the attribute that stores the result.</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_to</span> <span class="o">=</span> <span class="n">lookup</span> <span class="k">if</span> <span class="n">to_attr</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_to</span> <span class="o">=</span> <span class="n">LOOKUP_SEP</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">lookup</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="n">LOOKUP_SEP</span><span class="p">)[:</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span> <span class="o">+</span> <span class="p">[</span><span class="n">to_attr</span><span class="p">])</span> <span class="bp">self</span><span class="o">.</span><span class="n">queryset</span> <span class="o">=</span> <span class="n">queryset</span> <span class="bp">self</span><span class="o">.</span><span class="n">to_attr</span> <span class="o">=</span> <span class="n">to_attr</span> <span class="k">def</span> <span class="nf">add_prefix</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">prefix</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_through</span> <span class="o">=</span> <span class="n">LOOKUP_SEP</span><span class="o">.</span><span class="n">join</span><span class="p">([</span><span class="n">prefix</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_through</span><span class="p">])</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_to</span> <span class="o">=</span> <span class="n">LOOKUP_SEP</span><span class="o">.</span><span class="n">join</span><span class="p">([</span><span class="n">prefix</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_to</span><span class="p">])</span> <span class="k">def</span> <span class="nf">get_current_prefetch_through</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">level</span><span class="p">):</span> <span class="k">return</span> <span class="n">LOOKUP_SEP</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">prefetch_through</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="n">LOOKUP_SEP</span><span class="p">)[:</span><span class="n">level</span> <span class="o">+</span> <span class="mi">1</span><span class="p">])</span> <span class="k">def</span> <span class="nf">get_current_prefetch_to</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">level</span><span class="p">):</span> <span class="k">return</span> <span class="n">LOOKUP_SEP</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">prefetch_to</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="n">LOOKUP_SEP</span><span class="p">)[:</span><span class="n">level</span> <span class="o">+</span> <span class="mi">1</span><span class="p">])</span> <span class="k">def</span> <span class="nf">get_current_to_attr</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">level</span><span class="p">):</span> <span class="n">parts</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_to</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="n">LOOKUP_SEP</span><span class="p">)</span> <span class="n">to_attr</span> <span class="o">=</span> <span class="n">parts</span><span class="p">[</span><span class="n">level</span><span class="p">]</span> <span class="n">as_attr</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">to_attr</span> <span class="ow">and</span> <span class="n">level</span> <span class="o">==</span> <span class="nb">len</span><span class="p">(</span><span class="n">parts</span><span class="p">)</span> <span class="o">-</span> <span class="mi">1</span> <span class="k">return</span> <span class="n">to_attr</span><span class="p">,</span> <span class="n">as_attr</span> <span class="k">def</span> <span class="nf">get_current_queryset</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">level</span><span class="p">):</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_current_prefetch_to</span><span class="p">(</span><span class="n">level</span><span class="p">)</span> <span class="o">==</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_to</span><span class="p">:</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">queryset</span> <span class="k">return</span> <span class="kc">None</span> <span class="k">def</span> <span class="nf">__eq__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">other</span><span class="p">,</span> <span class="n">Prefetch</span><span class="p">):</span> <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">prefetch_to</span> <span class="o">==</span> <span class="n">other</span><span class="o">.</span><span class="n">prefetch_to</span> <span class="k">return</span> <span class="kc">False</span> <span class="k">def</span> <span class="nf">__hash__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span> <span class="k">return</span> <span class="nb">hash</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">__class__</span><span class="p">)</span> <span class="o">^</span> <span class="nb">hash</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">prefetch_to</span><span class="p">)</span></div> <span class="k">def</span> <span class="nf">normalize_prefetch_lookups</span><span class="p">(</span><span class="n">lookups</span><span class="p">,</span> <span class="n">prefix</span><span class="o">=</span><span class="kc">None</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Helper function that normalize lookups into Prefetch objects.</span> <span class="sd"> """</span> <span class="n">ret</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">lookup</span> <span class="ow">in</span> <span class="n">lookups</span><span class="p">:</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">lookup</span><span class="p">,</span> <span class="n">Prefetch</span><span class="p">):</span> <span class="n">lookup</span> <span class="o">=</span> <span class="n">Prefetch</span><span class="p">(</span><span class="n">lookup</span><span class="p">)</span> <span class="k">if</span> <span class="n">prefix</span><span class="p">:</span> <span class="n">lookup</span><span class="o">.</span><span class="n">add_prefix</span><span class="p">(</span><span class="n">prefix</span><span class="p">)</span> <span class="n">ret</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">lookup</span><span class="p">)</span> <span class="k">return</span> <span class="n">ret</span> <span class="k">def</span> <span class="nf">prefetch_related_objects</span><span class="p">(</span><span class="n">result_cache</span><span class="p">,</span> <span class="n">related_lookups</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Helper function for prefetch_related functionality</span> <span class="sd"> Populates prefetched objects caches for a list of results</span> <span class="sd"> from a QuerySet</span> <span class="sd"> """</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">result_cache</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span><span class="p">:</span> <span class="k">return</span> <span class="c1"># nothing to do</span> <span class="n">related_lookups</span> <span class="o">=</span> <span class="n">normalize_prefetch_lookups</span><span class="p">(</span><span class="n">related_lookups</span><span class="p">)</span> <span class="c1"># We need to be able to dynamically add to the list of prefetch_related</span> <span class="c1"># lookups that we look up (see below). So we need some book keeping to</span> <span class="c1"># ensure we don't do duplicate work.</span> <span class="n">done_queries</span> <span class="o">=</span> <span class="p">{}</span> <span class="c1"># dictionary of things like 'foo__bar': [results]</span> <span class="n">auto_lookups</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span> <span class="c1"># we add to this as we go through.</span> <span class="n">followed_descriptors</span> <span class="o">=</span> <span class="nb">set</span><span class="p">()</span> <span class="c1"># recursion protection</span> <span class="n">all_lookups</span> <span class="o">=</span> <span class="n">deque</span><span class="p">(</span><span class="n">related_lookups</span><span class="p">)</span> <span class="k">while</span> <span class="n">all_lookups</span><span class="p">:</span> <span class="n">lookup</span> <span class="o">=</span> <span class="n">all_lookups</span><span class="o">.</span><span class="n">popleft</span><span class="p">()</span> <span class="k">if</span> <span class="n">lookup</span><span class="o">.</span><span class="n">prefetch_to</span> <span class="ow">in</span> <span class="n">done_queries</span><span class="p">:</span> <span class="k">if</span> <span class="n">lookup</span><span class="o">.</span><span class="n">queryset</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"'</span><span class="si">%s</span><span class="s2">' lookup was already seen with a different queryset. "</span> <span class="s2">"You may need to adjust the ordering of your lookups."</span> <span class="o">%</span> <span class="n">lookup</span><span class="o">.</span><span class="n">prefetch_to</span><span class="p">)</span> <span class="k">continue</span> <span class="c1"># Top level, the list of objects to decorate is the result cache</span> <span class="c1"># from the primary QuerySet. It won't be for deeper levels.</span> <span class="n">obj_list</span> <span class="o">=</span> <span class="n">result_cache</span> <span class="n">through_attrs</span> <span class="o">=</span> <span class="n">lookup</span><span class="o">.</span><span class="n">prefetch_through</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="n">LOOKUP_SEP</span><span class="p">)</span> <span class="k">for</span> <span class="n">level</span><span class="p">,</span> <span class="n">through_attr</span> <span class="ow">in</span> <span class="nb">enumerate</span><span class="p">(</span><span class="n">through_attrs</span><span class="p">):</span> <span class="c1"># Prepare main instances</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">obj_list</span><span class="p">)</span> <span class="o">==</span> <span class="mi">0</span><span class="p">:</span> <span class="k">break</span> <span class="n">prefetch_to</span> <span class="o">=</span> <span class="n">lookup</span><span class="o">.</span><span class="n">get_current_prefetch_to</span><span class="p">(</span><span class="n">level</span><span class="p">)</span> <span class="k">if</span> <span class="n">prefetch_to</span> <span class="ow">in</span> <span class="n">done_queries</span><span class="p">:</span> <span class="c1"># Skip any prefetching, and any object preparation</span> <span class="n">obj_list</span> <span class="o">=</span> <span class="n">done_queries</span><span class="p">[</span><span class="n">prefetch_to</span><span class="p">]</span> <span class="k">continue</span> <span class="c1"># Prepare objects:</span> <span class="n">good_objects</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">obj_list</span><span class="p">:</span> <span class="c1"># Since prefetching can re-use instances, it is possible to have</span> <span class="c1"># the same instance multiple times in obj_list, so obj might</span> <span class="c1"># already be prepared.</span> <span class="k">if</span> <span class="ow">not</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="s1">'_prefetched_objects_cache'</span><span class="p">):</span> <span class="k">try</span><span class="p">:</span> <span class="n">obj</span><span class="o">.</span><span class="n">_prefetched_objects_cache</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">except</span> <span class="ne">AttributeError</span><span class="p">:</span> <span class="c1"># Must be in a QuerySet subclass that is not returning</span> <span class="c1"># Model instances, either in Django or 3rd</span> <span class="c1"># party. prefetch_related() doesn't make sense, so quit</span> <span class="c1"># now.</span> <span class="n">good_objects</span> <span class="o">=</span> <span class="kc">False</span> <span class="k">break</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">good_objects</span><span class="p">:</span> <span class="k">break</span> <span class="c1"># Descend down tree</span> <span class="c1"># We assume that objects retrieved are homogeneous (which is the premise</span> <span class="c1"># of prefetch_related), so what applies to first object applies to all.</span> <span class="n">first_obj</span> <span class="o">=</span> <span class="n">obj_list</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="n">prefetcher</span><span class="p">,</span> <span class="n">descriptor</span><span class="p">,</span> <span class="n">attr_found</span><span class="p">,</span> <span class="n">is_fetched</span> <span class="o">=</span> <span class="n">get_prefetcher</span><span class="p">(</span><span class="n">first_obj</span><span class="p">,</span> <span class="n">through_attr</span><span class="p">)</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">attr_found</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">AttributeError</span><span class="p">(</span><span class="s2">"Cannot find '</span><span class="si">%s</span><span class="s2">' on </span><span class="si">%s</span><span class="s2"> object, '</span><span class="si">%s</span><span class="s2">' is an invalid "</span> <span class="s2">"parameter to prefetch_related()"</span> <span class="o">%</span> <span class="p">(</span><span class="n">through_attr</span><span class="p">,</span> <span class="n">first_obj</span><span class="o">.</span><span class="n">__class__</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="n">lookup</span><span class="o">.</span><span class="n">prefetch_through</span><span class="p">))</span> <span class="k">if</span> <span class="n">level</span> <span class="o">==</span> <span class="nb">len</span><span class="p">(</span><span class="n">through_attrs</span><span class="p">)</span> <span class="o">-</span> <span class="mi">1</span> <span class="ow">and</span> <span class="n">prefetcher</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="c1"># Last one, this *must* resolve to something that supports</span> <span class="c1"># prefetching, otherwise there is no point adding it and the</span> <span class="c1"># developer asking for it has made a mistake.</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="s2">"'</span><span class="si">%s</span><span class="s2">' does not resolve to an item that supports "</span> <span class="s2">"prefetching - this is an invalid parameter to "</span> <span class="s2">"prefetch_related()."</span> <span class="o">%</span> <span class="n">lookup</span><span class="o">.</span><span class="n">prefetch_through</span><span class="p">)</span> <span class="k">if</span> <span class="n">prefetcher</span> <span class="ow">is</span> <span class="ow">not</span> <span class="kc">None</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">is_fetched</span><span class="p">:</span> <span class="n">obj_list</span><span class="p">,</span> <span class="n">additional_lookups</span> <span class="o">=</span> <span class="n">prefetch_one_level</span><span class="p">(</span><span class="n">obj_list</span><span class="p">,</span> <span class="n">prefetcher</span><span class="p">,</span> <span class="n">lookup</span><span class="p">,</span> <span class="n">level</span><span class="p">)</span> <span class="c1"># We need to ensure we don't keep adding lookups from the</span> <span class="c1"># same relationships to stop infinite recursion. So, if we</span> <span class="c1"># are already on an automatically added lookup, don't add</span> <span class="c1"># the new lookups from relationships we've seen already.</span> <span class="k">if</span> <span class="ow">not</span> <span class="p">(</span><span class="n">lookup</span> <span class="ow">in</span> <span class="n">auto_lookups</span> <span class="ow">and</span> <span class="n">descriptor</span> <span class="ow">in</span> <span class="n">followed_descriptors</span><span class="p">):</span> <span class="n">done_queries</span><span class="p">[</span><span class="n">prefetch_to</span><span class="p">]</span> <span class="o">=</span> <span class="n">obj_list</span> <span class="n">new_lookups</span> <span class="o">=</span> <span class="n">normalize_prefetch_lookups</span><span class="p">(</span><span class="n">additional_lookups</span><span class="p">,</span> <span class="n">prefetch_to</span><span class="p">)</span> <span class="n">auto_lookups</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">new_lookups</span><span class="p">)</span> <span class="n">all_lookups</span><span class="o">.</span><span class="n">extendleft</span><span class="p">(</span><span class="n">new_lookups</span><span class="p">)</span> <span class="n">followed_descriptors</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">descriptor</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># Either a singly related object that has already been fetched</span> <span class="c1"># (e.g. via select_related), or hopefully some other property</span> <span class="c1"># that doesn't support prefetching but needs to be traversed.</span> <span class="c1"># We replace the current list of parent objects with the list</span> <span class="c1"># of related objects, filtering out empty or missing values so</span> <span class="c1"># that we can continue with nullable or reverse relations.</span> <span class="n">new_obj_list</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">obj_list</span><span class="p">:</span> <span class="k">try</span><span class="p">:</span> <span class="n">new_obj</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">through_attr</span><span class="p">)</span> <span class="k">except</span> <span class="n">exceptions</span><span class="o">.</span><span class="n">ObjectDoesNotExist</span><span class="p">:</span> <span class="k">continue</span> <span class="k">if</span> <span class="n">new_obj</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="k">continue</span> <span class="c1"># We special-case `list` rather than something more generic</span> <span class="c1"># like `Iterable` because we don't want to accidentally match</span> <span class="c1"># user models that define __iter__.</span> <span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">new_obj</span><span class="p">,</span> <span class="nb">list</span><span class="p">):</span> <span class="n">new_obj_list</span><span class="o">.</span><span class="n">extend</span><span class="p">(</span><span class="n">new_obj</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">new_obj_list</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">new_obj</span><span class="p">)</span> <span class="n">obj_list</span> <span class="o">=</span> <span class="n">new_obj_list</span> <span class="k">def</span> <span class="nf">get_prefetcher</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">attr</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> For the attribute 'attr' on the given instance, finds</span> <span class="sd"> an object that has a get_prefetch_queryset().</span> <span class="sd"> Returns a 4 tuple containing:</span> <span class="sd"> (the object with get_prefetch_queryset (or None),</span> <span class="sd"> the descriptor object representing this relationship (or None),</span> <span class="sd"> a boolean that is False if the attribute was not found at all,</span> <span class="sd"> a boolean that is True if the attribute has already been fetched)</span> <span class="sd"> """</span> <span class="n">prefetcher</span> <span class="o">=</span> <span class="kc">None</span> <span class="n">is_fetched</span> <span class="o">=</span> <span class="kc">False</span> <span class="c1"># For singly related objects, we have to avoid getting the attribute</span> <span class="c1"># from the object, as this will trigger the query. So we first try</span> <span class="c1"># on the class, in order to get the descriptor object.</span> <span class="n">rel_obj_descriptor</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">instance</span><span class="o">.</span><span class="n">__class__</span><span class="p">,</span> <span class="n">attr</span><span class="p">,</span> <span class="kc">None</span><span class="p">)</span> <span class="k">if</span> <span class="n">rel_obj_descriptor</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">attr_found</span> <span class="o">=</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">attr</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">attr_found</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">if</span> <span class="n">rel_obj_descriptor</span><span class="p">:</span> <span class="c1"># singly related object, descriptor object has the</span> <span class="c1"># get_prefetch_queryset() method.</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">rel_obj_descriptor</span><span class="p">,</span> <span class="s1">'get_prefetch_queryset'</span><span class="p">):</span> <span class="n">prefetcher</span> <span class="o">=</span> <span class="n">rel_obj_descriptor</span> <span class="k">if</span> <span class="n">rel_obj_descriptor</span><span class="o">.</span><span class="n">is_cached</span><span class="p">(</span><span class="n">instance</span><span class="p">):</span> <span class="n">is_fetched</span> <span class="o">=</span> <span class="kc">True</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># descriptor doesn't support prefetching, so we go ahead and get</span> <span class="c1"># the attribute on the instance rather than the class to</span> <span class="c1"># support many related managers</span> <span class="n">rel_obj</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">instance</span><span class="p">,</span> <span class="n">attr</span><span class="p">)</span> <span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">rel_obj</span><span class="p">,</span> <span class="s1">'get_prefetch_queryset'</span><span class="p">):</span> <span class="n">prefetcher</span> <span class="o">=</span> <span class="n">rel_obj</span> <span class="k">return</span> <span class="n">prefetcher</span><span class="p">,</span> <span class="n">rel_obj_descriptor</span><span class="p">,</span> <span class="n">attr_found</span><span class="p">,</span> <span class="n">is_fetched</span> <span class="k">def</span> <span class="nf">prefetch_one_level</span><span class="p">(</span><span class="n">instances</span><span class="p">,</span> <span class="n">prefetcher</span><span class="p">,</span> <span class="n">lookup</span><span class="p">,</span> <span class="n">level</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> Helper function for prefetch_related_objects</span> <span class="sd"> Runs prefetches on all instances using the prefetcher object,</span> <span class="sd"> assigning results to relevant caches in instance.</span> <span class="sd"> The prefetched objects are returned, along with any additional</span> <span class="sd"> prefetches that must be done due to prefetch_related lookups</span> <span class="sd"> found from default managers.</span> <span class="sd"> """</span> <span class="c1"># prefetcher must have a method get_prefetch_queryset() which takes a list</span> <span class="c1"># of instances, and returns a tuple:</span> <span class="c1"># (queryset of instances of self.model that are related to passed in instances,</span> <span class="c1"># callable that gets value to be matched for returned instances,</span> <span class="c1"># callable that gets value to be matched for passed in instances,</span> <span class="c1"># boolean that is True for singly related objects,</span> <span class="c1"># cache name to assign to).</span> <span class="c1"># The 'values to be matched' must be hashable as they will be used</span> <span class="c1"># in a dictionary.</span> <span class="n">rel_qs</span><span class="p">,</span> <span class="n">rel_obj_attr</span><span class="p">,</span> <span class="n">instance_attr</span><span class="p">,</span> <span class="n">single</span><span class="p">,</span> <span class="n">cache_name</span> <span class="o">=</span> <span class="p">(</span> <span class="n">prefetcher</span><span class="o">.</span><span class="n">get_prefetch_queryset</span><span class="p">(</span><span class="n">instances</span><span class="p">,</span> <span class="n">lookup</span><span class="o">.</span><span class="n">get_current_queryset</span><span class="p">(</span><span class="n">level</span><span class="p">)))</span> <span class="c1"># We have to handle the possibility that the QuerySet we just got back</span> <span class="c1"># contains some prefetch_related lookups. We don't want to trigger the</span> <span class="c1"># prefetch_related functionality by evaluating the query. Rather, we need</span> <span class="c1"># to merge in the prefetch_related lookups.</span> <span class="n">additional_lookups</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">rel_qs</span><span class="p">,</span> <span class="s1">'_prefetch_related_lookups'</span><span class="p">,</span> <span class="p">[])</span> <span class="k">if</span> <span class="n">additional_lookups</span><span class="p">:</span> <span class="c1"># Don't need to clone because the manager should have given us a fresh</span> <span class="c1"># instance, so we access an internal instead of using public interface</span> <span class="c1"># for performance reasons.</span> <span class="n">rel_qs</span><span class="o">.</span><span class="n">_prefetch_related_lookups</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">all_related_objects</span> <span class="o">=</span> <span class="nb">list</span><span class="p">(</span><span class="n">rel_qs</span><span class="p">)</span> <span class="n">rel_obj_cache</span> <span class="o">=</span> <span class="p">{}</span> <span class="k">for</span> <span class="n">rel_obj</span> <span class="ow">in</span> <span class="n">all_related_objects</span><span class="p">:</span> <span class="n">rel_attr_val</span> <span class="o">=</span> <span class="n">rel_obj_attr</span><span class="p">(</span><span class="n">rel_obj</span><span class="p">)</span> <span class="n">rel_obj_cache</span><span class="o">.</span><span class="n">setdefault</span><span class="p">(</span><span class="n">rel_attr_val</span><span class="p">,</span> <span class="p">[])</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">rel_obj</span><span class="p">)</span> <span class="n">to_attr</span><span class="p">,</span> <span class="n">as_attr</span> <span class="o">=</span> <span class="n">lookup</span><span class="o">.</span><span class="n">get_current_to_attr</span><span class="p">(</span><span class="n">level</span><span class="p">)</span> <span class="c1"># Make sure `to_attr` does not conflict with a field.</span> <span class="k">if</span> <span class="n">as_attr</span> <span class="ow">and</span> <span class="n">instances</span><span class="p">:</span> <span class="c1"># We assume that objects retrieved are homogeneous (which is the premise</span> <span class="c1"># of prefetch_related), so what applies to first object applies to all.</span> <span class="n">model</span> <span class="o">=</span> <span class="n">instances</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span><span class="o">.</span><span class="n">__class__</span> <span class="k">try</span><span class="p">:</span> <span class="n">model</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">get_field</span><span class="p">(</span><span class="n">to_attr</span><span class="p">)</span> <span class="k">except</span> <span class="n">exceptions</span><span class="o">.</span><span class="n">FieldDoesNotExist</span><span class="p">:</span> <span class="k">pass</span> <span class="k">else</span><span class="p">:</span> <span class="n">msg</span> <span class="o">=</span> <span class="s1">'to_attr=</span><span class="si">{}</span><span class="s1"> conflicts with a field on the </span><span class="si">{}</span><span class="s1"> model.'</span> <span class="k">raise</span> <span class="ne">ValueError</span><span class="p">(</span><span class="n">msg</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">to_attr</span><span class="p">,</span> <span class="n">model</span><span class="o">.</span><span class="n">__name__</span><span class="p">))</span> <span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">instances</span><span class="p">:</span> <span class="n">instance_attr_val</span> <span class="o">=</span> <span class="n">instance_attr</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span> <span class="n">vals</span> <span class="o">=</span> <span class="n">rel_obj_cache</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="n">instance_attr_val</span><span class="p">,</span> <span class="p">[])</span> <span class="k">if</span> <span class="n">single</span><span class="p">:</span> <span class="n">val</span> <span class="o">=</span> <span class="n">vals</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="k">if</span> <span class="n">vals</span> <span class="k">else</span> <span class="kc">None</span> <span class="n">to_attr</span> <span class="o">=</span> <span class="n">to_attr</span> <span class="k">if</span> <span class="n">as_attr</span> <span class="k">else</span> <span class="n">cache_name</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">to_attr</span><span class="p">,</span> <span class="n">val</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="k">if</span> <span class="n">as_attr</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">to_attr</span><span class="p">,</span> <span class="n">vals</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="c1"># Cache in the QuerySet.all().</span> <span class="n">qs</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">to_attr</span><span class="p">)</span><span class="o">.</span><span class="n">all</span><span class="p">()</span> <span class="n">qs</span><span class="o">.</span><span class="n">_result_cache</span> <span class="o">=</span> <span class="n">vals</span> <span class="c1"># We don't want the individual qs doing prefetch_related now,</span> <span class="c1"># since we have merged this into the current work.</span> <span class="n">qs</span><span class="o">.</span><span class="n">_prefetch_done</span> <span class="o">=</span> <span class="kc">True</span> <span class="n">obj</span><span class="o">.</span><span class="n">_prefetched_objects_cache</span><span class="p">[</span><span class="n">cache_name</span><span class="p">]</span> <span class="o">=</span> <span class="n">qs</span> <span class="k">return</span> <span class="n">all_related_objects</span><span class="p">,</span> <span class="n">additional_lookups</span> <span class="k">class</span> <span class="nc">RelatedPopulator</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span> <span class="sd">"""</span> <span class="sd"> RelatedPopulator is used for select_related() object instantiation.</span> <span class="sd"> The idea is that each select_related() model will be populated by a</span> <span class="sd"> different RelatedPopulator instance. The RelatedPopulator instances get</span> <span class="sd"> klass_info and select (computed in SQLCompiler) plus the used db as</span> <span class="sd"> input for initialization. That data is used to compute which columns</span> <span class="sd"> to use, how to instantiate the model, and how to populate the links</span> <span class="sd"> between the objects.</span> <span class="sd"> The actual creation of the objects is done in populate() method. This</span> <span class="sd"> method gets row and from_obj as input and populates the select_related()</span> <span class="sd"> model instance.</span> <span class="sd"> """</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">klass_info</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">db</span><span class="p">):</span> <span class="bp">self</span><span class="o">.</span><span class="n">db</span> <span class="o">=</span> <span class="n">db</span> <span class="c1"># Pre-compute needed attributes. The attributes are:</span> <span class="c1"># - model_cls: the possibly deferred model class to instantiate</span> <span class="c1"># - either:</span> <span class="c1"># - cols_start, cols_end: usually the columns in the row are</span> <span class="c1"># in the same order model_cls.__init__ expects them, so we</span> <span class="c1"># can instantiate by model_cls(*row[cols_start:cols_end])</span> <span class="c1"># - reorder_for_init: When select_related descends to a child</span> <span class="c1"># class, then we want to reuse the already selected parent</span> <span class="c1"># data. However, in this case the parent data isn't necessarily</span> <span class="c1"># in the same order that Model.__init__ expects it to be, so</span> <span class="c1"># we have to reorder the parent data. The reorder_for_init</span> <span class="c1"># attribute contains a function used to reorder the field data</span> <span class="c1"># in the order __init__ expects it.</span> <span class="c1"># - pk_idx: the index of the primary key field in the reordered</span> <span class="c1"># model data. Used to check if a related object exists at all.</span> <span class="c1"># - init_list: the field attnames fetched from the database. For</span> <span class="c1"># deferred models this isn't the same as all attnames of the</span> <span class="c1"># model's fields.</span> <span class="c1"># - related_populators: a list of RelatedPopulator instances if</span> <span class="c1"># select_related() descends to related models from this model.</span> <span class="c1"># - cache_name, reverse_cache_name: the names to use for setattr</span> <span class="c1"># when assigning the fetched object to the from_obj. If the</span> <span class="c1"># reverse_cache_name is set, then we also set the reverse link.</span> <span class="n">select_fields</span> <span class="o">=</span> <span class="n">klass_info</span><span class="p">[</span><span class="s1">'select_fields'</span><span class="p">]</span> <span class="n">from_parent</span> <span class="o">=</span> <span class="n">klass_info</span><span class="p">[</span><span class="s1">'from_parent'</span><span class="p">]</span> <span class="k">if</span> <span class="ow">not</span> <span class="n">from_parent</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">cols_start</span> <span class="o">=</span> <span class="n">select_fields</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="bp">self</span><span class="o">.</span><span class="n">cols_end</span> <span class="o">=</span> <span class="n">select_fields</span><span class="p">[</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span> <span class="o">+</span> <span class="mi">1</span> <span class="bp">self</span><span class="o">.</span><span class="n">init_list</span> <span class="o">=</span> <span class="p">[</span> <span class="n">f</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span><span class="o">.</span><span class="n">target</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">select</span><span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">cols_start</span><span class="p">:</span><span class="bp">self</span><span class="o">.</span><span class="n">cols_end</span><span class="p">]</span> <span class="p">]</span> <span class="bp">self</span><span class="o">.</span><span class="n">reorder_for_init</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">else</span><span class="p">:</span> <span class="n">model_init_attnames</span> <span class="o">=</span> <span class="p">[</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">klass_info</span><span class="p">[</span><span class="s1">'model'</span><span class="p">]</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span> <span class="p">]</span> <span class="n">reorder_map</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">idx</span> <span class="ow">in</span> <span class="n">select_fields</span><span class="p">:</span> <span class="n">field</span> <span class="o">=</span> <span class="n">select</span><span class="p">[</span><span class="n">idx</span><span class="p">][</span><span class="mi">0</span><span class="p">]</span><span class="o">.</span><span class="n">target</span> <span class="n">init_pos</span> <span class="o">=</span> <span class="n">model_init_attnames</span><span class="o">.</span><span class="n">index</span><span class="p">(</span><span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="n">reorder_map</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">init_pos</span><span class="p">,</span> <span class="n">field</span><span class="o">.</span><span class="n">attname</span><span class="p">,</span> <span class="n">idx</span><span class="p">))</span> <span class="n">reorder_map</span><span class="o">.</span><span class="n">sort</span><span class="p">()</span> <span class="bp">self</span><span class="o">.</span><span class="n">init_list</span> <span class="o">=</span> <span class="p">[</span><span class="n">v</span><span class="p">[</span><span class="mi">1</span><span class="p">]</span> <span class="k">for</span> <span class="n">v</span> <span class="ow">in</span> <span class="n">reorder_map</span><span class="p">]</span> <span class="n">pos_list</span> <span class="o">=</span> <span class="p">[</span><span class="n">row_pos</span> <span class="k">for</span> <span class="n">_</span><span class="p">,</span> <span class="n">_</span><span class="p">,</span> <span class="n">row_pos</span> <span class="ow">in</span> <span class="n">reorder_map</span><span class="p">]</span> <span class="k">def</span> <span class="nf">reorder_for_init</span><span class="p">(</span><span class="n">row</span><span class="p">):</span> <span class="k">return</span> <span class="p">[</span><span class="n">row</span><span class="p">[</span><span class="n">row_pos</span><span class="p">]</span> <span class="k">for</span> <span class="n">row_pos</span> <span class="ow">in</span> <span class="n">pos_list</span><span class="p">]</span> <span class="bp">self</span><span class="o">.</span><span class="n">reorder_for_init</span> <span class="o">=</span> <span class="n">reorder_for_init</span> <span class="bp">self</span><span class="o">.</span><span class="n">model_cls</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">get_deferred_cls</span><span class="p">(</span><span class="n">klass_info</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">init_list</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">pk_idx</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">init_list</span><span class="o">.</span><span class="n">index</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">model_cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">pk</span><span class="o">.</span><span class="n">attname</span><span class="p">)</span> <span class="bp">self</span><span class="o">.</span><span class="n">related_populators</span> <span class="o">=</span> <span class="n">get_related_populators</span><span class="p">(</span><span class="n">klass_info</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">)</span> <span class="n">field</span> <span class="o">=</span> <span class="n">klass_info</span><span class="p">[</span><span class="s1">'field'</span><span class="p">]</span> <span class="n">reverse</span> <span class="o">=</span> <span class="n">klass_info</span><span class="p">[</span><span class="s1">'reverse'</span><span class="p">]</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_cache_name</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">if</span> <span class="n">reverse</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">cache_name</span> <span class="o">=</span> <span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">()</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_cache_name</span> <span class="o">=</span> <span class="n">field</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">()</span> <span class="k">else</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">cache_name</span> <span class="o">=</span> <span class="n">field</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">()</span> <span class="k">if</span> <span class="n">field</span><span class="o">.</span><span class="n">unique</span><span class="p">:</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_cache_name</span> <span class="o">=</span> <span class="n">field</span><span class="o">.</span><span class="n">rel</span><span class="o">.</span><span class="n">get_cache_name</span><span class="p">()</span> <span class="k">def</span> <span class="nf">get_deferred_cls</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">klass_info</span><span class="p">,</span> <span class="n">init_list</span><span class="p">):</span> <span class="n">model_cls</span> <span class="o">=</span> <span class="n">klass_info</span><span class="p">[</span><span class="s1">'model'</span><span class="p">]</span> <span class="k">if</span> <span class="nb">len</span><span class="p">(</span><span class="n">init_list</span><span class="p">)</span> <span class="o">!=</span> <span class="nb">len</span><span class="p">(</span><span class="n">model_cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span><span class="p">):</span> <span class="n">init_set</span> <span class="o">=</span> <span class="nb">set</span><span class="p">(</span><span class="n">init_list</span><span class="p">)</span> <span class="n">skip</span> <span class="o">=</span> <span class="p">[</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="k">for</span> <span class="n">f</span> <span class="ow">in</span> <span class="n">model_cls</span><span class="o">.</span><span class="n">_meta</span><span class="o">.</span><span class="n">concrete_fields</span> <span class="k">if</span> <span class="n">f</span><span class="o">.</span><span class="n">attname</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">init_set</span> <span class="p">]</span> <span class="n">model_cls</span> <span class="o">=</span> <span class="n">deferred_class_factory</span><span class="p">(</span><span class="n">model_cls</span><span class="p">,</span> <span class="n">skip</span><span class="p">)</span> <span class="k">return</span> <span class="n">model_cls</span> <span class="k">def</span> <span class="nf">populate</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">row</span><span class="p">,</span> <span class="n">from_obj</span><span class="p">):</span> <span class="k">if</span> <span class="bp">self</span><span class="o">.</span><span class="n">reorder_for_init</span><span class="p">:</span> <span class="n">obj_data</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">reorder_for_init</span><span class="p">(</span><span class="n">row</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">obj_data</span> <span class="o">=</span> <span class="n">row</span><span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">cols_start</span><span class="p">:</span><span class="bp">self</span><span class="o">.</span><span class="n">cols_end</span><span class="p">]</span> <span class="k">if</span> <span class="n">obj_data</span><span class="p">[</span><span class="bp">self</span><span class="o">.</span><span class="n">pk_idx</span><span class="p">]</span> <span class="ow">is</span> <span class="kc">None</span><span class="p">:</span> <span class="n">obj</span> <span class="o">=</span> <span class="kc">None</span> <span class="k">else</span><span class="p">:</span> <span class="n">obj</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">model_cls</span><span class="o">.</span><span class="n">from_db</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">db</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">init_list</span><span class="p">,</span> <span class="n">obj_data</span><span class="p">)</span> <span class="k">if</span> <span class="n">obj</span> <span class="ow">and</span> <span class="bp">self</span><span class="o">.</span><span class="n">related_populators</span><span class="p">:</span> <span class="k">for</span> <span class="n">rel_iter</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">related_populators</span><span class="p">:</span> <span class="n">rel_iter</span><span class="o">.</span><span class="n">populate</span><span class="p">(</span><span class="n">row</span><span class="p">,</span> <span class="n">obj</span><span class="p">)</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">from_obj</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">cache_name</span><span class="p">,</span> <span class="n">obj</span><span class="p">)</span> <span class="k">if</span> <span class="n">obj</span> <span class="ow">and</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_cache_name</span><span class="p">:</span> <span class="nb">setattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">reverse_cache_name</span><span class="p">,</span> <span class="n">from_obj</span><span class="p">)</span> <span class="k">def</span> <span class="nf">get_related_populators</span><span class="p">(</span><span class="n">klass_info</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">db</span><span class="p">):</span> <span class="n">iterators</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">related_klass_infos</span> <span class="o">=</span> <span class="n">klass_info</span><span class="o">.</span><span class="n">get</span><span class="p">(</span><span class="s1">'related_klass_infos'</span><span class="p">,</span> <span class="p">[])</span> <span class="k">for</span> <span class="n">rel_klass_info</span> <span class="ow">in</span> <span class="n">related_klass_infos</span><span class="p">:</span> <span class="n">rel_cls</span> <span class="o">=</span> <span class="n">RelatedPopulator</span><span class="p">(</span><span class="n">rel_klass_info</span><span class="p">,</span> <span class="n">select</span><span class="p">,</span> <span class="n">db</span><span class="p">)</span> <span class="n">iterators</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">rel_cls</span><span class="p">)</span> <span class="k">return</span> <span class="n">iterators</span> </pre></div> </div> </div> </div> <div class="yui-b" id="sidebar"> <div class="sphinxsidebar" role="navigation" aria-label="main navigation"> <div class="sphinxsidebarwrapper"> <h3>Browse</h3> <ul> </ul> <h3>You are here:</h3> <ul> <li> <a href="../../../../index.html">Django 1.8.19 documentation</a> 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