doc/src/sgml/ref/drop_opclass.sgml

   1 <!--
   2 $PostgreSQL$
   3 PostgreSQL documentation
   4 -->
   5
   6 <refentry id="SQL-DROPOPCLASS">
   7  <refmeta>
   8   <refentrytitle id="SQL-DROPOPCLASS-TITLE">DROP OPERATOR CLASS</refentrytitle>
   9   <manvolnum>7</manvolnum>
  10   <refmiscinfo>SQL - Language Statements</refmiscinfo>
  11  </refmeta>
  12
  13  <refnamediv>
  14   <refname>DROP OPERATOR CLASS</refname>
  15   <refpurpose>remove an operator class</refpurpose>
  16  </refnamediv>
  17
  18  <indexterm zone="sql-dropopclass">
  19   <primary>DROP OPERATOR CLASS</primary>
  20  </indexterm>
  21
  22  <refsynopsisdiv>
  23 <synopsis>
  24 DROP OPERATOR CLASS [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable> USING <replaceable class="PARAMETER">index_method</replaceable> [ CASCADE | RESTRICT ]
  25 </synopsis>
  26  </refsynopsisdiv>
  27
  28  <refsect1>
  29   <title>Description</title>
  30
  31   <para>
  32    <command>DROP OPERATOR CLASS</command> drops an existing operator class.
  33    To execute this command you must be the owner of the operator class.
  34   </para>
  35
  36   <para>
  37    <command>DROP OPERATOR CLASS</command> does not drop any of the operators
  38    or functions referenced by the class.  If there are any indexes depending
  39    on the operator class, you will need to specify
  40    <literal>CASCADE</> for the drop to complete.
  41   </para>
  42  </refsect1>
  43
  44  <refsect1>
  45   <title>Parameters</title>
  46
  47   <variablelist>
  48
  49    <varlistentry>
  50     <term><literal>IF EXISTS</literal></term>
  51     <listitem>
  52      <para>
  53       Do not throw an error if the operator class does not exist. A notice is issued
  54       in this case.
  55      </para>
  56     </listitem>
  57    </varlistentry>
  58
  59    <varlistentry>
  60     <term><replaceable class="parameter">name</replaceable></term>
  61     <listitem>
  62      <para>
  63       The name (optionally schema-qualified) of an existing operator class.
  64      </para>
  65     </listitem>
  66    </varlistentry>
  67
  68    <varlistentry>
  69     <term><replaceable class="parameter">index_method</replaceable></term>
  70     <listitem>
  71      <para>
  72       The name of the index access method the operator class is for.
  73      </para>
  74     </listitem>
  75    </varlistentry>
  76
  77    <varlistentry>
  78     <term><literal>CASCADE</literal></term>
  79     <listitem>
  80      <para>
  81       Automatically drop objects that depend on the operator class.
  82      </para>
  83     </listitem>
  84    </varlistentry>
  85
  86    <varlistentry>
  87     <term><literal>RESTRICT</literal></term>
  88     <listitem>
  89      <para>
  90       Refuse to drop the operator class if any objects depend on it.
  91       This is the default.
  92      </para>
  93     </listitem>
  94    </varlistentry>
  95   </variablelist>
  96  </refsect1>
  97
  98  <refsect1>
  99   <title>Notes</title>
 100
 101   <para>
 102    <command>DROP OPERATOR CLASS</> will not drop the operator family
 103    containing the class, even if there is nothing else left in the
 104    family (in particular, in the case where the family was implicitly
 105    created by <command>CREATE OPERATOR CLASS</>).  An empty operator
 106    family is harmless, but for the sake of tidiness you might wish to
 107    remove the family with <command>DROP OPERATOR FAMILY</>; or perhaps
 108    better, use <command>DROP OPERATOR FAMILY</> in the first place.
 109   </para>
 110  </refsect1>
 111
 112  <refsect1>
 113   <title>Examples</title>
 114
 115   <para>
 116    Remove the B-tree operator class <literal>widget_ops</literal>:
 117
 118 <programlisting>
 119 DROP OPERATOR CLASS widget_ops USING btree;
 120 </programlisting>
 121
 122    This command will not succeed if there are any existing indexes
 123    that use the operator class.  Add <literal>CASCADE</> to drop
 124    such indexes along with the operator class.
 125   </para>
 126  </refsect1>
 127
 128  <refsect1>
 129   <title>Compatibility</title>
 130
 131   <para>
 132    There is no <command>DROP OPERATOR CLASS</command> statement in the
 133    SQL standard.
 134   </para>
 135  </refsect1>
 136
 137  <refsect1>
 138   <title>See Also</title>
 139
 140   <simplelist type="inline">
 141    <member><xref linkend="sql-alteropclass" endterm="sql-alteropclass-title"></member>
 142    <member><xref linkend="sql-createopclass" endterm="sql-createopclass-title"></member>
 143    <member><xref linkend="sql-dropopfamily" endterm="sql-dropopfamily-title"></member>
 144   </simplelist>
 145  </refsect1>
 146
 147 </refentry>