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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>DROP OPERATOR CLASS</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="sql-dropoperator.html" title="DROP OPERATOR" /><link rel="next" href="sql-dropopfamily.html" title="DROP OPERATOR FAMILY" /></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">DROP OPERATOR CLASS</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-dropoperator.html" title="DROP OPERATOR">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</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="sql-dropopfamily.html" title="DROP OPERATOR FAMILY">Next</a></td></tr></table><hr></hr></div><div class="refentry" id="SQL-DROPOPCLASS"><div class="titlepage"></div><a id="id-1.9.3.120.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">DROP OPERATOR CLASS</span></h2><p>DROP OPERATOR CLASS — remove an operator class</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">
  3. DROP OPERATOR CLASS [ IF EXISTS ] <em class="replaceable"><code>name</code></em> USING <em class="replaceable"><code>index_method</code></em> [ CASCADE | RESTRICT ]
  4. </pre></div><div class="refsect1" id="id-1.9.3.120.5"><h2>Description</h2><p>
  5. <code class="command">DROP OPERATOR CLASS</code> drops an existing operator class.
  6. To execute this command you must be the owner of the operator class.
  7. </p><p>
  8. <code class="command">DROP OPERATOR CLASS</code> does not drop any of the operators
  9. or functions referenced by the class. If there are any indexes depending
  10. on the operator class, you will need to specify
  11. <code class="literal">CASCADE</code> for the drop to complete.
  12. </p></div><div class="refsect1" id="id-1.9.3.120.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">IF EXISTS</code></span></dt><dd><p>
  13. Do not throw an error if the operator class does not exist. A notice is issued
  14. in this case.
  15. </p></dd><dt><span class="term"><em class="replaceable"><code>name</code></em></span></dt><dd><p>
  16. The name (optionally schema-qualified) of an existing operator class.
  17. </p></dd><dt><span class="term"><em class="replaceable"><code>index_method</code></em></span></dt><dd><p>
  18. The name of the index access method the operator class is for.
  19. </p></dd><dt><span class="term"><code class="literal">CASCADE</code></span></dt><dd><p>
  20. Automatically drop objects that depend on the operator class (such as
  21. indexes), and in turn all objects that depend on those objects
  22. (see <a class="xref" href="ddl-depend.html" title="5.14. Dependency Tracking">Section 5.14</a>).
  23. </p></dd><dt><span class="term"><code class="literal">RESTRICT</code></span></dt><dd><p>
  24. Refuse to drop the operator class if any objects depend on it.
  25. This is the default.
  26. </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.120.7"><h2>Notes</h2><p>
  27. <code class="command">DROP OPERATOR CLASS</code> will not drop the operator family
  28. containing the class, even if there is nothing else left in the
  29. family (in particular, in the case where the family was implicitly
  30. created by <code class="command">CREATE OPERATOR CLASS</code>). An empty operator
  31. family is harmless, but for the sake of tidiness you might wish to
  32. remove the family with <code class="command">DROP OPERATOR FAMILY</code>; or perhaps
  33. better, use <code class="command">DROP OPERATOR FAMILY</code> in the first place.
  34. </p></div><div class="refsect1" id="id-1.9.3.120.8"><h2>Examples</h2><p>
  35. Remove the B-tree operator class <code class="literal">widget_ops</code>:
  36. </p><pre class="programlisting">
  37. DROP OPERATOR CLASS widget_ops USING btree;
  38. </pre><p>
  39. This command will not succeed if there are any existing indexes
  40. that use the operator class. Add <code class="literal">CASCADE</code> to drop
  41. such indexes along with the operator class.
  42. </p></div><div class="refsect1" id="id-1.9.3.120.9"><h2>Compatibility</h2><p>
  43. There is no <code class="command">DROP OPERATOR CLASS</code> statement in the
  44. SQL standard.
  45. </p></div><div class="refsect1" id="id-1.9.3.120.10"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-alteropclass.html" title="ALTER OPERATOR CLASS"><span class="refentrytitle">ALTER OPERATOR CLASS</span></a>, <a class="xref" href="sql-createopclass.html" title="CREATE OPERATOR CLASS"><span class="refentrytitle">CREATE OPERATOR CLASS</span></a>, <a class="xref" href="sql-dropopfamily.html" title="DROP OPERATOR FAMILY"><span class="refentrytitle">DROP OPERATOR FAMILY</span></a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-dropoperator.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-dropopfamily.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">DROP OPERATOR </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> DROP OPERATOR FAMILY</td></tr></table></div></body></html>
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