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<!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"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>52.15. pg_database</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="catalog-pg-conversion.html" title="52.14. pg_conversion" /><link rel="next" href="catalog-pg-db-role-setting.html" title="52.16. pg_db_role_setting" /></head><body><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">52.15. <code xmlns="http://www.w3.org/1999/xhtml" class="structname">pg_database</code></th></tr><tr><td width="10%" align="left"><a accesskey="p" href="catalog-pg-conversion.html" title="52.14. pg_conversion">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="catalogs.html" title="Chapter 52. System Catalogs">Up</a></td><th width="60%" align="center">Chapter 52. System Catalogs</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 11.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="catalog-pg-db-role-setting.html" title="52.16. pg_db_role_setting">Next</a></td></tr></table><hr></hr></div><div class="sect1" id="CATALOG-PG-DATABASE"><div class="titlepage"><div><div><h2 class="title" style="clear: both">52.15. <code class="structname">pg_database</code></h2></div></div></div><a id="id-1.10.4.17.2" class="indexterm"></a><p>
The catalog <code class="structname">pg_database</code> stores information about
the available databases. Databases are created with the <a class="xref" href="sql-createdatabase.html" title="CREATE DATABASE"><span class="refentrytitle">CREATE DATABASE</span></a> command.
Consult <a class="xref" href="managing-databases.html" title="Chapter 22. Managing Databases">Chapter 22</a> for details about the meaning
of some of the parameters.
</p><p>
Unlike most system catalogs, <code class="structname">pg_database</code>
is shared across all databases of a cluster: there is only one
copy of <code class="structname">pg_database</code> per cluster, not
one per database.
</p><div class="table" id="id-1.10.4.17.5"><p class="title"><strong>Table 52.15. <code class="structname">pg_database</code> Columns</strong></p><div class="table-contents"><table class="table" summary="pg_database Columns" border="1"><colgroup><col /><col /><col /><col /></colgroup><thead><tr><th>Name</th><th>Type</th><th>References</th><th>Description</th></tr></thead><tbody><tr><td><code class="structfield">oid</code></td><td><code class="type">oid</code></td><td> </td><td>Row identifier (hidden attribute; must be explicitly selected)</td></tr><tr><td><code class="structfield">datname</code></td><td><code class="type">name</code></td><td> </td><td>Database name</td></tr><tr><td><code class="structfield">datdba</code></td><td><code class="type">oid</code></td><td><code class="literal"><a class="link" href="catalog-pg-authid.html" title="52.8. pg_authid"><code class="structname">pg_authid</code></a>.oid</code></td><td>Owner of the database, usually the user who created it</td></tr><tr><td><code class="structfield">encoding</code></td><td><code class="type">int4</code></td><td> </td><td>Character encoding for this database
(<code class="function">pg_encoding_to_char()</code> can translate
this number to the encoding name)</td></tr><tr><td><code class="structfield">datcollate</code></td><td><code class="type">name</code></td><td> </td><td>LC_COLLATE for this database</td></tr><tr><td><code class="structfield">datctype</code></td><td><code class="type">name</code></td><td> </td><td>LC_CTYPE for this database</td></tr><tr><td><code class="structfield">datistemplate</code></td><td><code class="type">bool</code></td><td> </td><td>
If true, then this database can be cloned by
any user with <code class="literal">CREATEDB</code> privileges;
if false, then only superusers or the owner of
the database can clone it.
</td></tr><tr><td><code class="structfield">datallowconn</code></td><td><code class="type">bool</code></td><td> </td><td>
If false then no one can connect to this database. This is
used to protect the <code class="literal">template0</code> database from being altered.
</td></tr><tr><td><code class="structfield">datconnlimit</code></td><td><code class="type">int4</code></td><td> </td><td>
Sets maximum number of concurrent connections that can be made
to this database. -1 means no limit.
</td></tr><tr><td><code class="structfield">datlastsysoid</code></td><td><code class="type">oid</code></td><td> </td><td>
Last system OID in the database; useful
particularly to <span class="application">pg_dump</span>
</td></tr><tr><td><code class="structfield">datfrozenxid</code></td><td><code class="type">xid</code></td><td> </td><td>
All transaction IDs before this one have been replaced with a permanent
(<span class="quote">“<span class="quote">frozen</span>”</span>) transaction ID in this database. This is used to
track whether the database needs to be vacuumed in order to prevent
transaction ID wraparound or to allow <code class="literal">pg_xact</code> to be shrunk.
It is the minimum of the per-table
<code class="structname">pg_class</code>.<code class="structfield">relfrozenxid</code> values.
</td></tr><tr><td><code class="structfield">datminmxid</code></td><td><code class="type">xid</code></td><td> </td><td>
All multixact IDs before this one have been replaced with a
transaction ID in this database. This is used to
track whether the database needs to be vacuumed in order to prevent
multixact ID wraparound or to allow <code class="literal">pg_multixact</code> to be shrunk.
It is the minimum of the per-table
<code class="structname">pg_class</code>.<code class="structfield">relminmxid</code> values.
</td></tr><tr><td><code class="structfield">dattablespace</code></td><td><code class="type">oid</code></td><td><code class="literal"><a class="link" href="catalog-pg-tablespace.html" title="52.54. pg_tablespace"><code class="structname">pg_tablespace</code></a>.oid</code></td><td>
The default tablespace for the database.
Within this database, all tables for which
<code class="structname">pg_class</code>.<code class="structfield">reltablespace</code> is zero
will be stored in this tablespace; in particular, all the non-shared
system catalogs will be there.
</td></tr><tr><td><code class="structfield">datacl</code></td><td><code class="type">aclitem[]</code></td><td> </td><td>
Access privileges; see
<a class="xref" href="sql-grant.html" title="GRANT"><span class="refentrytitle">GRANT</span></a> and
<a class="xref" href="sql-revoke.html" title="REVOKE"><span class="refentrytitle">REVOKE</span></a>
for details
</td></tr></tbody></table></div></div><br class="table-break" /></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="catalog-pg-conversion.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="catalogs.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="catalog-pg-db-role-setting.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">52.14. <code class="structname">pg_conversion</code> </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 52.16. <code class="structname">pg_db_role_setting</code></td></tr></table></div></body></html>
