drop_rule.sgml

postgresql8.3.4源码,开源数据库

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<refentry id="SQL-DROPRULE">
 <refmeta>
  <refentrytitle id="SQL-DROPRULE-TITLE">DROP RULE</refentrytitle>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>DROP RULE</refname>
  <refpurpose>remove a rewrite rule</refpurpose>
 </refnamediv>

 <indexterm zone="sql-droprule">
  <primary>DROP RULE</primary>
 </indexterm>

 <refsynopsisdiv>
<synopsis>
DROP RULE [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable> ON <replaceable class="PARAMETER">relation</replaceable> [ CASCADE | RESTRICT ]
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <command>DROP RULE</command> drops a rewrite rule.
  </para>
 </refsect1>

 <refsect1>
  <title>Parameters</title>

  <variablelist>

   <varlistentry>
    <term><literal>IF EXISTS</literal></term>
    <listitem>
     <para>
      Do not throw an error if the rule does not exist. A notice is issued 
      in this case.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">name</replaceable></term>
    <listitem>
     <para>
      The name of the rule to drop.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">relation</replaceable></term>
    <listitem>
     <para>
      The name (optionally schema-qualified) of the table or view that
      the rule applies to.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>CASCADE</literal></term>
    <listitem>
     <para>
      Automatically drop objects that depend on the rule.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal>RESTRICT</literal></term>
    <listitem>
     <para>
      Refuse to drop the rule if any objects depend on it.  This is
      the default.
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect1>

 <refsect1>
  <title>Examples</title>

  <para>
   To drop the rewrite rule <literal>newrule</literal>:

<programlisting>
DROP RULE newrule ON mytable;
</programlisting>
  </para>
 </refsect1>
 
 <refsect1>
  <title>Compatibility</title>

  <para>
   There is no <command>DROP RULE</command> statement in the SQL standard.
  </para>
 </refsect1>

 <refsect1>
  <title>See Also</title>

  <simplelist type="inline">
   <member><xref linkend="sql-createrule" endterm="sql-createrule-title"></member>
  </simplelist>
 </refsect1>

</refentry>