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  1. <?xml version="1.0" encoding="UTF-8" standalone="no"?>
  2. <!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>22.4. Database Configuration</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 V1.79.1" /><link rel="prev" href="manage-ag-templatedbs.html" title="22.3. Template Databases" /><link rel="next" href="manage-ag-dropdb.html" title="22.5. Destroying a Database" /></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">22.4. Database Configuration</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="manage-ag-templatedbs.html" title="22.3. Template Databases">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="managing-databases.html" title="Chapter 22. Managing Databases">Up</a></td><th width="60%" align="center">Chapter 22. Managing Databases</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 12.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="manage-ag-dropdb.html" title="22.5. Destroying a Database">Next</a></td></tr></table><hr></hr></div><div class="sect1" id="MANAGE-AG-CONFIG"><div class="titlepage"><div><div><h2 class="title" style="clear: both">22.4. Database Configuration</h2></div></div></div><p>
  3. Recall from <a class="xref" href="runtime-config.html" title="Chapter 19. Server Configuration">Chapter 19</a> that the
  4. <span class="productname">PostgreSQL</span> server provides a large number of
  5. run-time configuration variables. You can set database-specific
  6. default values for many of these settings.
  7. </p><p>
  8. For example, if for some reason you want to disable the
  9. <acronym class="acronym">GEQO</acronym> optimizer for a given database, you'd
  10. ordinarily have to either disable it for all databases or make sure
  11. that every connecting client is careful to issue <code class="literal">SET geqo
  12. TO off</code>. To make this setting the default within a particular
  13. database, you can execute the command:
  14. </p><pre class="programlisting">
  15. ALTER DATABASE mydb SET geqo TO off;
  16. </pre><p>
  17. This will save the setting (but not set it immediately). In
  18. subsequent connections to this database it will appear as though
  19. <code class="literal">SET geqo TO off;</code> had been executed just before the
  20. session started.
  21. Note that users can still alter this setting during their sessions; it
  22. will only be the default. To undo any such setting, use
  23. <code class="literal">ALTER DATABASE <em class="replaceable"><code>dbname</code></em> RESET
  24. <em class="replaceable"><code>varname</code></em></code>.
  25. </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="manage-ag-templatedbs.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="managing-databases.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="manage-ag-dropdb.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">22.3. Template Databases </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> 22.5. Destroying a Database</td></tr></table></div></body></html>
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