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<div class="section" id="s-module-django.contrib.gis.db.models">
<span id="s-geodjango-database-api"></span><span id="s-ref-gis-db-api"></span><span id="module-django.contrib.gis.db.models"></span><span id="geodjango-database-api"></span><span id="ref-gis-db-api"></span><h1>GeoDjango Database API<a class="headerlink" href="#module-django.contrib.gis.db.models" title="Permalink to this headline">¶</a></h1>
<div class="section" id="s-spatial-backends">
<span id="s-id1"></span><span id="spatial-backends"></span><span id="id1"></span><h2>Spatial Backends<a class="headerlink" href="#spatial-backends" title="Permalink to this headline">¶</a></h2>
<div class="versionadded">
<span class="title">New in Django 1.2:</span> <a class="reference internal" href="../../../releases/1.2.html"><em>Please see the release notes</em></a></div>
<p>In Django 1.2, support for <a class="reference internal" href="../../../topics/db/multi-db.html"><em>multiple databases</em></a> was
introduced. In order to support multiple databases, GeoDjango has segregated
its functionality into full-fledged spatial database backends:</p>
<ul class="simple">
<li><tt class="xref py py-mod docutils literal"><span class="pre">django.contrib.gis.db.backends.postgis</span></tt></li>
<li><tt class="xref py py-mod docutils literal"><span class="pre">django.contrib.gis.db.backends.mysql</span></tt></li>
<li><tt class="xref py py-mod docutils literal"><span class="pre">django.contrib.gis.db.backends.oracle</span></tt></li>
<li><tt class="xref py py-mod docutils literal"><span class="pre">django.contrib.gis.db.backends.spatialite</span></tt></li>
</ul>
<div class="section" id="s-mysql-spatial-limitations">
<span id="s-id2"></span><span id="mysql-spatial-limitations"></span><span id="id2"></span><h3>MySQL Spatial Limitations<a class="headerlink" href="#mysql-spatial-limitations" title="Permalink to this headline">¶</a></h3>
<p>MySQL’s spatial extensions only support bounding box operations
(what MySQL calls minimum bounding rectangles, or MBR). Specifically,
<a class="reference external" href="http://dev.mysql.com/doc/refman/5.1/en/functions-for-testing-spatial-relations-between-geometric-objects.html">MySQL does not conform to the OGC standard</a>:</p>
<blockquote>
<div>Currently, MySQL does not implement these functions
[<tt class="docutils literal"><span class="pre">Contains</span></tt>, <tt class="docutils literal"><span class="pre">Crosses</span></tt>, <tt class="docutils literal"><span class="pre">Disjoint</span></tt>, <tt class="docutils literal"><span class="pre">Intersects</span></tt>, <tt class="docutils literal"><span class="pre">Overlaps</span></tt>,
<tt class="docutils literal"><span class="pre">Touches</span></tt>, <tt class="docutils literal"><span class="pre">Within</span></tt>]
according to the specification. Those that are implemented return
the same result as the corresponding MBR-based functions.</div></blockquote>
<p>In other words, while spatial lookups such as <a class="reference internal" href="geoquerysets.html#std:fieldlookup-gis-contains"><tt class="xref std std-lookup docutils literal"><span class="pre">contains</span></tt></a>
are available in GeoDjango when using MySQL, the results returned are really
equivalent to what would be returned when using <a class="reference internal" href="geoquerysets.html#std:fieldlookup-bbcontains"><tt class="xref std std-lookup docutils literal"><span class="pre">bbcontains</span></tt></a>
on a different spatial backend.</p>
<div class="admonition warning">
<p class="first admonition-title">Warning</p>
<p class="last">True spatial indexes (R-trees) are only supported with
MyISAM tables on MySQL. <a class="footnote-reference" href="#fnmysqlidx" id="id3">[6]</a> In other words, when using
MySQL spatial extensions you have to choose between fast spatial
lookups and the integrity of your data – MyISAM tables do
not support transactions or foreign key constraints.</p>
</div>
</div>
</div>
<div class="section" id="s-creating-and-saving-geographic-models">
<span id="creating-and-saving-geographic-models"></span><h2>Creating and Saving Geographic Models<a class="headerlink" href="#creating-and-saving-geographic-models" title="Permalink to this headline">¶</a></h2>
<p>Here is an example of how to create a geometry object (assuming the <tt class="docutils literal"><span class="pre">Zipcode</span></tt>
model):</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">zipcode.models</span> <span class="kn">import</span> <span class="n">Zipcode</span>
<span class="gp">>>> </span><span class="n">z</span> <span class="o">=</span> <span class="n">Zipcode</span><span class="p">(</span><span class="n">code</span><span class="o">=</span><span class="mi">77096</span><span class="p">,</span> <span class="n">poly</span><span class="o">=</span><span class="s">'POLYGON(( 10 10, 10 20, 20 20, 20 15, 10 10))'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">z</span><span class="o">.</span><span class="n">save</span><span class="p">()</span>
</pre></div>
</div>
<p><a class="reference internal" href="geos.html#django.contrib.gis.geos.GEOSGeometry" title="django.contrib.gis.geos.GEOSGeometry"><tt class="xref py py-class docutils literal"><span class="pre">GEOSGeometry</span></tt></a> objects may also be used to save geometric models:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">django.contrib.gis.geos</span> <span class="kn">import</span> <span class="n">GEOSGeometry</span>
<span class="gp">>>> </span><span class="n">poly</span> <span class="o">=</span> <span class="n">GEOSGeometry</span><span class="p">(</span><span class="s">'POLYGON(( 10 10, 10 20, 20 20, 20 15, 10 10))'</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">z</span> <span class="o">=</span> <span class="n">Zipcode</span><span class="p">(</span><span class="n">code</span><span class="o">=</span><span class="mi">77096</span><span class="p">,</span> <span class="n">poly</span><span class="o">=</span><span class="n">poly</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">z</span><span class="o">.</span><span class="n">save</span><span class="p">()</span>
</pre></div>
</div>
<p>Moreover, if the <tt class="docutils literal"><span class="pre">GEOSGeometry</span></tt> is in a different coordinate system (has a
different SRID value) than that of the field, then it will be implicitly
transformed into the SRID of the model’s field, using the spatial database’s
transform procedure:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">poly_3084</span> <span class="o">=</span> <span class="n">GEOSGeometry</span><span class="p">(</span><span class="s">'POLYGON(( 10 10, 10 20, 20 20, 20 15, 10 10))'</span><span class="p">,</span> <span class="n">srid</span><span class="o">=</span><span class="mi">3084</span><span class="p">)</span> <span class="c"># SRID 3084 is 'NAD83(HARN) / Texas Centric Lambert Conformal'</span>
<span class="gp">>>> </span><span class="n">z</span> <span class="o">=</span> <span class="n">Zipcode</span><span class="p">(</span><span class="n">code</span><span class="o">=</span><span class="mi">78212</span><span class="p">,</span> <span class="n">poly</span><span class="o">=</span><span class="n">poly_3084</span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">z</span><span class="o">.</span><span class="n">save</span><span class="p">()</span>
<span class="gp">>>> </span><span class="kn">from</span> <span class="nn">django.db</span> <span class="kn">import</span> <span class="n">connection</span>
<span class="gp">>>> </span><span class="k">print</span> <span class="n">connection</span><span class="o">.</span><span class="n">queries</span><span class="p">[</span><span class="o">-</span><span class="mi">1</span><span class="p">][</span><span class="s">'sql'</span><span class="p">]</span> <span class="c"># printing the last SQL statement executed (requires DEBUG=True)</span>
<span class="go">INSERT INTO "geoapp_zipcode" ("code", "poly") VALUES (78212, ST_Transform(ST_GeomFromWKB('\\001 ... ', 3084), 4326))</span>
</pre></div>
</div>
<p>Thus, geometry parameters may be passed in using the <tt class="docutils literal"><span class="pre">GEOSGeometry</span></tt> object, WKT
(Well Known Text <a class="footnote-reference" href="#fnwkt" id="id4">[1]</a>), HEXEWKB (PostGIS specific – a WKB geometry in
hexadecimal <a class="footnote-reference" href="#fnewkb" id="id5">[2]</a>), and GeoJSON <a class="footnote-reference" href="#fngeojson" id="id6">[3]</a> (requires GDAL). Essentially,
if the input is not a <tt class="docutils literal"><span class="pre">GEOSGeometry</span></tt> object, the geometry field will attempt to
create a <tt class="docutils literal"><span class="pre">GEOSGeometry</span></tt> instance from the input.</p>
<p>For more information creating <a class="reference internal" href="geos.html#django.contrib.gis.geos.GEOSGeometry" title="django.contrib.gis.geos.GEOSGeometry"><tt class="xref py py-class docutils literal"><span class="pre">GEOSGeometry</span></tt></a>
objects, refer to the <a class="reference internal" href="geos.html#geos-tutorial"><em>GEOS tutorial</em></a>.</p>
</div>
<div class="section" id="s-spatial-lookups">
<span id="s-spatial-lookups-intro"></span><span id="spatial-lookups"></span><span id="spatial-lookups-intro"></span><h2>Spatial Lookups<a class="headerlink" href="#spatial-lookups" title="Permalink to this headline">¶</a></h2>
<p>GeoDjango’s lookup types may be used with any manager method like
<tt class="docutils literal"><span class="pre">filter()</span></tt>, <tt class="docutils literal"><span class="pre">exclude()</span></tt>, etc. However, the lookup types unique to
GeoDjango are only available on geometry fields.
Filters on ‘normal’ fields (e.g. <a class="reference internal" href="../../models/fields.html#django.db.models.CharField" title="django.db.models.CharField"><tt class="xref py py-class docutils literal"><span class="pre">CharField</span></tt></a>)
may be chained with those on geographic fields. Thus, geographic queries
take the following general form (assuming the <tt class="docutils literal"><span class="pre">Zipcode</span></tt> model used in the
<a class="reference internal" href="model-api.html#ref-gis-model-api"><em>GeoDjango Model API</em></a>):</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">qs</span> <span class="o">=</span> <span class="n">Zipcode</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="o"><</span><span class="n">field</span><span class="o">></span><span class="n">__</span><span class="o"><</span><span class="n">lookup_type</span><span class="o">>=<</span><span class="n">parameter</span><span class="o">></span><span class="p">)</span>
<span class="gp">>>> </span><span class="n">qs</span> <span class="o">=</span> <span class="n">Zipcode</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">exclude</span><span class="p">(</span><span class="o">...</span><span class="p">)</span>
</pre></div>
</div>
<p>For example:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="n">qs</span> <span class="o">=</span> <span class="n">Zipcode</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">poly__contains</span><span class="o">=</span><span class="n">pnt</span><span class="p">)</span>
</pre></div>
</div>
<p>In this case, <tt class="docutils literal"><span class="pre">poly</span></tt> is the geographic field, <a class="reference internal" href="geoquerysets.html#std:fieldlookup-gis-contains"><tt class="xref std std-lookup docutils literal"><span class="pre">contains</span></tt></a>
is the spatial lookup type, and <tt class="docutils literal"><span class="pre">pnt</span></tt> is the parameter (which may be a
<a class="reference internal" href="geos.html#django.contrib.gis.geos.GEOSGeometry" title="django.contrib.gis.geos.GEOSGeometry"><tt class="xref py py-class docutils literal"><span class="pre">GEOSGeometry</span></tt></a> object or a string of
GeoJSON , WKT, or HEXEWKB).</p>
<p>A complete reference can be found in the <a class="reference internal" href="geoquerysets.html#spatial-lookups"><em>spatial lookup reference</em></a>.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">GeoDjango constructs spatial SQL with the <a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet" title="django.contrib.gis.db.models.GeoQuerySet"><tt class="xref py py-class docutils literal"><span class="pre">GeoQuerySet</span></tt></a>, a
subclass of <a class="reference internal" href="../../models/querysets.html#django.db.models.query.QuerySet" title="django.db.models.query.QuerySet"><tt class="xref py py-class docutils literal"><span class="pre">QuerySet</span></tt></a>. The
<a class="reference internal" href="model-api.html#django.contrib.gis.db.models.GeoManager" title="django.contrib.gis.db.models.GeoManager"><tt class="xref py py-class docutils literal"><span class="pre">GeoManager</span></tt></a> instance attached to your model is what
enables use of <a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet" title="django.contrib.gis.db.models.GeoQuerySet"><tt class="xref py py-class docutils literal"><span class="pre">GeoQuerySet</span></tt></a>.</p>
</div>
</div>
<div class="section" id="s-distance-queries">
<span id="s-id7"></span><span id="distance-queries"></span><span id="id7"></span><h2>Distance Queries<a class="headerlink" href="#distance-queries" title="Permalink to this headline">¶</a></h2>
<div class="section" id="s-introduction">
<span id="introduction"></span><h3>Introduction<a class="headerlink" href="#introduction" title="Permalink to this headline">¶</a></h3>
<p>Distance calculations with spatial data is tricky because, unfortunately,
the Earth is not flat. Some distance queries with fields in a geographic
coordinate system may have to be expressed differently because of
limitations in PostGIS. Please see the <a class="reference internal" href="model-api.html#selecting-an-srid"><em>Selecting an SRID</em></a> section
in the <a class="reference internal" href="model-api.html#ref-gis-model-api"><em>GeoDjango Model API</em></a> documentation for more details.</p>
</div>
<div class="section" id="s-distance-lookups">
<span id="s-distance-lookups-intro"></span><span id="distance-lookups"></span><span id="distance-lookups-intro"></span><h3>Distance Lookups<a class="headerlink" href="#distance-lookups" title="Permalink to this headline">¶</a></h3>
<p><em>Availability</em>: PostGIS, Oracle, SpatiaLite</p>
<p>The following distance lookups are available:</p>
<ul class="simple">
<li><a class="reference internal" href="geoquerysets.html#std:fieldlookup-distance_lt"><tt class="xref std std-lookup docutils literal"><span class="pre">distance_lt</span></tt></a></li>
<li><a class="reference internal" href="geoquerysets.html#std:fieldlookup-distance_lte"><tt class="xref std std-lookup docutils literal"><span class="pre">distance_lte</span></tt></a></li>
<li><a class="reference internal" href="geoquerysets.html#std:fieldlookup-distance_gt"><tt class="xref std std-lookup docutils literal"><span class="pre">distance_gt</span></tt></a></li>
<li><a class="reference internal" href="geoquerysets.html#std:fieldlookup-distance_gte"><tt class="xref std std-lookup docutils literal"><span class="pre">distance_gte</span></tt></a></li>
<li><a class="reference internal" href="geoquerysets.html#std:fieldlookup-dwithin"><tt class="xref std std-lookup docutils literal"><span class="pre">dwithin</span></tt></a></li>
</ul>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">For <em>measuring</em>, rather than querying on distances, use the
<a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.distance" title="django.contrib.gis.db.models.GeoQuerySet.distance"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.distance()</span></tt></a> method.</p>
</div>
<p>Distance lookups take a tuple parameter comprising:</p>
<ol class="arabic simple">
<li>A geometry to base calculations from; and</li>
<li>A number or <a class="reference internal" href="measure.html#django.contrib.gis.measure.Distance" title="django.contrib.gis.measure.Distance"><tt class="xref py py-class docutils literal"><span class="pre">Distance</span></tt></a> object containing the distance.</li>
</ol>
<p>If a <a class="reference internal" href="measure.html#django.contrib.gis.measure.Distance" title="django.contrib.gis.measure.Distance"><tt class="xref py py-class docutils literal"><span class="pre">Distance</span></tt></a> object is used,
it may be expressed in any units (the SQL generated will use units
converted to those of the field); otherwise, numeric parameters are assumed
to be in the units of the field.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">For users of PostGIS 1.4 and below, the routine <tt class="docutils literal"><span class="pre">ST_Distance_Sphere</span></tt>
is used by default for calculating distances on geographic coordinate systems
(e.g., WGS84) – which may only be called with point geometries <a class="footnote-reference" href="#fndistsphere14" id="id8">[4]</a>.
Thus, geographic distance lookups on traditional PostGIS geometry columns are
only allowed on <a class="reference internal" href="model-api.html#django.contrib.gis.db.models.PointField" title="django.contrib.gis.db.models.PointField"><tt class="xref py py-class docutils literal"><span class="pre">PointField</span></tt></a> model fields using a point for the
geometry parameter.</p>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p>In PostGIS 1.5, <tt class="docutils literal"><span class="pre">ST_Distance_Sphere</span></tt> does <em>not</em> limit the geometry types
geographic distance queries are performed with. <a class="footnote-reference" href="#fndistsphere15" id="id9">[5]</a> However,
these queries may take a long time, as great-circle distances must be
calculated on the fly for <em>every</em> row in the query. This is because the
spatial index on traditional geometry fields cannot be used.</p>
<p class="last">For much better performance on WGS84 distance queries, consider using
<a class="reference internal" href="model-api.html#geography-type"><em>geography columns</em></a> in your database instead because
they are able to use their spatial index in distance queries.
You can tell GeoDjango to use a geography column by setting <tt class="docutils literal"><span class="pre">geography=True</span></tt>
in your field definition.</p>
</div>
<p>For example, let’s say we have a <tt class="docutils literal"><span class="pre">SouthTexasCity</span></tt> model (from the
<a class="reference external" href="https://code.djangoproject.com/browser/django/trunk/django/contrib/gis/tests/distapp/models.py">GeoDjango distance tests</a> ) on a <em>projected</em> coordinate system valid for cities
in southern Texas:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="kn">from</span> <span class="nn">django.contrib.gis.db</span> <span class="kn">import</span> <span class="n">models</span>
<span class="k">class</span> <span class="nc">SouthTexasCity</span><span class="p">(</span><span class="n">models</span><span class="o">.</span><span class="n">Model</span><span class="p">):</span>
<span class="n">name</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">CharField</span><span class="p">(</span><span class="n">max_length</span><span class="o">=</span><span class="mi">30</span><span class="p">)</span>
<span class="c"># A projected coordinate system (only valid for South Texas!)</span>
<span class="c"># is used, units are in meters.</span>
<span class="n">point</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">PointField</span><span class="p">(</span><span class="n">srid</span><span class="o">=</span><span class="mi">32140</span><span class="p">)</span>
<span class="n">objects</span> <span class="o">=</span> <span class="n">models</span><span class="o">.</span><span class="n">GeoManager</span><span class="p">()</span>
</pre></div>
</div>
<p>Then distance queries may be performed as follows:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="gp">>>> </span><span class="kn">from</span> <span class="nn">django.contrib.gis.geos</span> <span class="kn">import</span> <span class="o">*</span>
<span class="gp">>>> </span><span class="kn">from</span> <span class="nn">django.contrib.gis.measure</span> <span class="kn">import</span> <span class="n">D</span> <span class="c"># ``D`` is a shortcut for ``Distance``</span>
<span class="gp">>>> </span><span class="kn">from</span> <span class="nn">geoapp</span> <span class="kn">import</span> <span class="n">SouthTexasCity</span>
<span class="go"># Distances will be calculated from this point, which does not have to be projected.</span>
<span class="gp">>>> </span><span class="n">pnt</span> <span class="o">=</span> <span class="n">fromstr</span><span class="p">(</span><span class="s">'POINT(-96.876369 29.905320)'</span><span class="p">,</span> <span class="n">srid</span><span class="o">=</span><span class="mi">4326</span><span class="p">)</span>
<span class="go"># If numeric parameter, units of field (meters in this case) are assumed.</span>
<span class="gp">>>> </span><span class="n">qs</span> <span class="o">=</span> <span class="n">SouthTexasCity</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">point__distance_lte</span><span class="o">=</span><span class="p">(</span><span class="n">pnt</span><span class="p">,</span> <span class="mi">7000</span><span class="p">))</span>
<span class="go"># Find all Cities within 7 km, > 20 miles away, and > 100 chains away (an obscure unit)</span>
<span class="gp">>>> </span><span class="n">qs</span> <span class="o">=</span> <span class="n">SouthTexasCity</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">point__distance_lte</span><span class="o">=</span><span class="p">(</span><span class="n">pnt</span><span class="p">,</span> <span class="n">D</span><span class="p">(</span><span class="n">km</span><span class="o">=</span><span class="mi">7</span><span class="p">)))</span>
<span class="gp">>>> </span><span class="n">qs</span> <span class="o">=</span> <span class="n">SouthTexasCity</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">point__distance_gte</span><span class="o">=</span><span class="p">(</span><span class="n">pnt</span><span class="p">,</span> <span class="n">D</span><span class="p">(</span><span class="n">mi</span><span class="o">=</span><span class="mi">20</span><span class="p">)))</span>
<span class="gp">>>> </span><span class="n">qs</span> <span class="o">=</span> <span class="n">SouthTexasCity</span><span class="o">.</span><span class="n">objects</span><span class="o">.</span><span class="n">filter</span><span class="p">(</span><span class="n">point__distance_gte</span><span class="o">=</span><span class="p">(</span><span class="n">pnt</span><span class="p">,</span> <span class="n">D</span><span class="p">(</span><span class="n">chain</span><span class="o">=</span><span class="mi">100</span><span class="p">)))</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="s-compatibility-tables">
<span id="s-compatibility-table"></span><span id="compatibility-tables"></span><span id="compatibility-table"></span><h2>Compatibility Tables<a class="headerlink" href="#compatibility-tables" title="Permalink to this headline">¶</a></h2>
<div class="section" id="s-spatial-lookup-compatibility">
<span id="s-id11"></span><span id="spatial-lookup-compatibility"></span><span id="id11"></span><h3>Spatial Lookups<a class="headerlink" href="#spatial-lookup-compatibility" title="Permalink to this headline">¶</a></h3>
<p>The following table provides a summary of what spatial lookups are available
for each spatial database backend.</p>
<table class="docutils">
<colgroup>
<col width="46%" />
<col width="13%" />
<col width="11%" />
<col width="17%" />
<col width="14%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Lookup Type</th>
<th class="head">PostGIS</th>
<th class="head">Oracle</th>
<th class="head">MySQL <a class="footnote-reference" href="#id13" id="id12">[7]</a></th>
<th class="head">SpatiaLite</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-bbcontains"><tt class="xref std std-lookup docutils literal"><span class="pre">bbcontains</span></tt></a></td>
<td>X</td>
<td> </td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-bboverlaps"><tt class="xref std std-lookup docutils literal"><span class="pre">bboverlaps</span></tt></a></td>
<td>X</td>
<td> </td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-contained"><tt class="xref std std-lookup docutils literal"><span class="pre">contained</span></tt></a></td>
<td>X</td>
<td> </td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-gis-contains"><tt class="xref std std-lookup docutils literal"><span class="pre">contains</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-contains_properly"><tt class="xref std std-lookup docutils literal"><span class="pre">contains_properly</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-coveredby"><tt class="xref std std-lookup docutils literal"><span class="pre">coveredby</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-covers"><tt class="xref std std-lookup docutils literal"><span class="pre">covers</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-crosses"><tt class="xref std std-lookup docutils literal"><span class="pre">crosses</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-disjoint"><tt class="xref std std-lookup docutils literal"><span class="pre">disjoint</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-distance_gt"><tt class="xref std std-lookup docutils literal"><span class="pre">distance_gt</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-distance_gte"><tt class="xref std std-lookup docutils literal"><span class="pre">distance_gte</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-distance_lt"><tt class="xref std std-lookup docutils literal"><span class="pre">distance_lt</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-distance_lte"><tt class="xref std std-lookup docutils literal"><span class="pre">distance_lte</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-dwithin"><tt class="xref std std-lookup docutils literal"><span class="pre">dwithin</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-equals"><tt class="xref std std-lookup docutils literal"><span class="pre">equals</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="../../models/querysets.html#std:fieldlookup-exact"><tt class="xref std std-lookup docutils literal"><span class="pre">exact</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-intersects"><tt class="xref std std-lookup docutils literal"><span class="pre">intersects</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-overlaps"><tt class="xref std std-lookup docutils literal"><span class="pre">overlaps</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-relate"><tt class="xref std std-lookup docutils literal"><span class="pre">relate</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-same_as"><tt class="xref std std-lookup docutils literal"><span class="pre">same_as</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-touches"><tt class="xref std std-lookup docutils literal"><span class="pre">touches</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-within"><tt class="xref std std-lookup docutils literal"><span class="pre">within</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-left"><tt class="xref std std-lookup docutils literal"><span class="pre">left</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-right"><tt class="xref std std-lookup docutils literal"><span class="pre">right</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-overlaps_left"><tt class="xref std std-lookup docutils literal"><span class="pre">overlaps_left</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-overlaps_right"><tt class="xref std std-lookup docutils literal"><span class="pre">overlaps_right</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-overlaps_above"><tt class="xref std std-lookup docutils literal"><span class="pre">overlaps_above</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-overlaps_below"><tt class="xref std std-lookup docutils literal"><span class="pre">overlaps_below</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-strictly_above"><tt class="xref std std-lookup docutils literal"><span class="pre">strictly_above</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#std:fieldlookup-strictly_below"><tt class="xref std std-lookup docutils literal"><span class="pre">strictly_below</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
<td> </td>
</tr>
</tbody>
</table>
</div>
<div class="section" id="s-geoqueryset-methods">
<span id="s-geoqueryset-method-compatibility"></span><span id="geoqueryset-methods"></span><span id="geoqueryset-method-compatibility"></span><h3><tt class="docutils literal"><span class="pre">GeoQuerySet</span></tt> Methods<a class="headerlink" href="#geoqueryset-methods" title="Permalink to this headline">¶</a></h3>
<p>The following table provides a summary of what <a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet" title="django.contrib.gis.db.models.GeoQuerySet"><tt class="xref py py-class docutils literal"><span class="pre">GeoQuerySet</span></tt></a> methods
are available on each spatial backend. Please note that MySQL does not
support any of these methods, and is thus excluded from the table.</p>
<table class="docutils">
<colgroup>
<col width="61%" />
<col width="12%" />
<col width="10%" />
<col width="17%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Method</th>
<th class="head">PostGIS</th>
<th class="head">Oracle</th>
<th class="head">SpatiaLite</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.area" title="django.contrib.gis.db.models.GeoQuerySet.area"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.area()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.centroid" title="django.contrib.gis.db.models.GeoQuerySet.centroid"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.centroid()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.collect" title="django.contrib.gis.db.models.GeoQuerySet.collect"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.collect()</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.difference" title="django.contrib.gis.db.models.GeoQuerySet.difference"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.difference()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.distance" title="django.contrib.gis.db.models.GeoQuerySet.distance"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.distance()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.envelope" title="django.contrib.gis.db.models.GeoQuerySet.envelope"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.envelope()</span></tt></a></td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.extent" title="django.contrib.gis.db.models.GeoQuerySet.extent"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.extent()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.extent3d" title="django.contrib.gis.db.models.GeoQuerySet.extent3d"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.extent3d()</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.force_rhr" title="django.contrib.gis.db.models.GeoQuerySet.force_rhr"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.force_rhr()</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.geohash" title="django.contrib.gis.db.models.GeoQuerySet.geohash"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.geohash()</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.geojson" title="django.contrib.gis.db.models.GeoQuerySet.geojson"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.geojson()</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.gml" title="django.contrib.gis.db.models.GeoQuerySet.gml"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.gml()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.intersection" title="django.contrib.gis.db.models.GeoQuerySet.intersection"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.intersection()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.kml" title="django.contrib.gis.db.models.GeoQuerySet.kml"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.kml()</span></tt></a></td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.length" title="django.contrib.gis.db.models.GeoQuerySet.length"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.length()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.make_line" title="django.contrib.gis.db.models.GeoQuerySet.make_line"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.make_line()</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.mem_size" title="django.contrib.gis.db.models.GeoQuerySet.mem_size"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.mem_size()</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.num_geom" title="django.contrib.gis.db.models.GeoQuerySet.num_geom"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.num_geom()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.num_points" title="django.contrib.gis.db.models.GeoQuerySet.num_points"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.num_points()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.perimeter" title="django.contrib.gis.db.models.GeoQuerySet.perimeter"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.perimeter()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.point_on_surface" title="django.contrib.gis.db.models.GeoQuerySet.point_on_surface"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.point_on_surface()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.reverse_geom" title="django.contrib.gis.db.models.GeoQuerySet.reverse_geom"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.reverse_geom()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.scale" title="django.contrib.gis.db.models.GeoQuerySet.scale"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.scale()</span></tt></a></td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.snap_to_grid" title="django.contrib.gis.db.models.GeoQuerySet.snap_to_grid"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.snap_to_grid()</span></tt></a></td>
<td>X</td>
<td> </td>
<td> </td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.svg" title="django.contrib.gis.db.models.GeoQuerySet.svg"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.svg()</span></tt></a></td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.sym_difference" title="django.contrib.gis.db.models.GeoQuerySet.sym_difference"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.sym_difference()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.transform" title="django.contrib.gis.db.models.GeoQuerySet.transform"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.transform()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.translate" title="django.contrib.gis.db.models.GeoQuerySet.translate"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.translate()</span></tt></a></td>
<td>X</td>
<td> </td>
<td>X</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.union" title="django.contrib.gis.db.models.GeoQuerySet.union"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.union()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="geoquerysets.html#django.contrib.gis.db.models.GeoQuerySet.unionagg" title="django.contrib.gis.db.models.GeoQuerySet.unionagg"><tt class="xref py py-meth docutils literal"><span class="pre">GeoQuerySet.unionagg()</span></tt></a></td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
</tbody>
</table>
<p class="rubric">Footnotes</p>
<table class="docutils footnote" frame="void" id="fnwkt" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id4">[1]</a></td><td><em>See</em> Open Geospatial Consortium, Inc., <a class="reference external" href="http://www.opengis.org/docs/99-049.pdf">OpenGIS Simple Feature Specification For SQL</a>, Document 99-049 (May 5, 1999), at Ch. 3.2.5, p. 3-11 (SQL Textual Representation of Geometry).</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="fnewkb" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id5">[2]</a></td><td><em>See</em> <a class="reference external" href="http://postgis.refractions.net/documentation/manual-1.5/ch04.html#EWKB_EWKT">PostGIS EWKB, EWKT and Canonical Forms</a>, PostGIS documentation at Ch. 4.1.2.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="fngeojson" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id6">[3]</a></td><td><em>See</em> Howard Butler, Martin Daly, Allan Doyle, Tim Schaub, & Christopher Schmidt, <a class="reference external" href="http://geojson.org/geojson-spec.html">The GeoJSON Format Specification</a>, Revision 1.0 (June 16, 2008).</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="fndistsphere14" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id8">[4]</a></td><td><em>See</em> <a class="reference external" href="http://postgis.refractions.net/documentation/manual-1.4/ST_Distance_Sphere.html">PostGIS 1.4 documentation</a> on <tt class="docutils literal"><span class="pre">ST_distance_sphere</span></tt>.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="fndistsphere15" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id9">[5]</a></td><td><em>See</em> <a class="reference external" href="http://postgis.refractions.net/documentation/manual-1.5/ST_Distance_Sphere.html">PostGIS 1.5 documentation</a> on <tt class="docutils literal"><span class="pre">ST_distance_sphere</span></tt>.</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="fnmysqlidx" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id3">[6]</a></td><td><p class="first"><em>See</em> <a class="reference external" href="http://dev.mysql.com/doc/refman/5.1/en/creating-spatial-indexes.html">Creating Spatial Indexes</a>
in the MySQL 5.1 Reference Manual:</p>
<blockquote class="last">
<div>For MyISAM tables, <tt class="docutils literal"><span class="pre">SPATIAL</span> <span class="pre">INDEX</span></tt> creates an R-tree index. For storage
engines that support nonspatial indexing of spatial columns, the engine
creates a B-tree index. A B-tree index on spatial values will be useful
for exact-value lookups, but not for range scans.</div></blockquote>
</td></tr>
</tbody>
</table>
<table class="docutils footnote" frame="void" id="id13" rules="none">
<colgroup><col class="label" /><col /></colgroup>
<tbody valign="top">
<tr><td class="label"><a class="fn-backref" href="#id12">[7]</a></td><td>Refer <a class="reference internal" href="#mysql-spatial-limitations"><em>MySQL Spatial Limitations</em></a> section for more details.</td></tr>
</tbody>
</table>
</div>
</div>
</div>
</div>
</div>
</div>
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<h3><a href="../../../contents.html">Table Of Contents</a></h3>
<ul>
<li><a class="reference internal" href="#">GeoDjango Database API</a><ul>
<li><a class="reference internal" href="#spatial-backends">Spatial Backends</a><ul>
<li><a class="reference internal" href="#mysql-spatial-limitations">MySQL Spatial Limitations</a></li>
</ul>
</li>
<li><a class="reference internal" href="#creating-and-saving-geographic-models">Creating and Saving Geographic Models</a></li>
<li><a class="reference internal" href="#spatial-lookups">Spatial Lookups</a></li>
<li><a class="reference internal" href="#distance-queries">Distance Queries</a><ul>
<li><a class="reference internal" href="#introduction">Introduction</a></li>
<li><a class="reference internal" href="#distance-lookups">Distance Lookups</a></li>
</ul>
</li>
<li><a class="reference internal" href="#compatibility-tables">Compatibility Tables</a><ul>
<li><a class="reference internal" href="#spatial-lookup-compatibility">Spatial Lookups</a></li>
<li><a class="reference internal" href="#geoqueryset-methods"><tt class="docutils literal"><span class="pre">GeoQuerySet</span></tt> Methods</a></li>
</ul>
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