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  • Committer: Bazaar Package Importer
  • Author(s): Martin Pitt
  • Date: 2011-05-11 10:41:53 UTC
  • Revision ID: james.westby@ubuntu.com-20110511104153-psbh2o58553fv1m0
Tags: upstream-9.1~beta1
Import upstream version 9.1~beta1

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doc/src/sgml/ref/release_savepoint.sgml
 
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<!--
 
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doc/src/sgml/ref/release_savepoint.sgml
 
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PostgreSQL documentation
 
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-->
 
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<refentry id="SQL-RELEASE-SAVEPOINT">
 
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 <refmeta>
 
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  <refentrytitle>RELEASE SAVEPOINT</refentrytitle>
 
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  <manvolnum>7</manvolnum>
 
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  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 
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 </refmeta>
 
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 <refnamediv>
 
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  <refname>RELEASE SAVEPOINT</refname>
 
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  <refpurpose>destroy a previously defined savepoint</refpurpose>
 
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 </refnamediv>
 
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 <indexterm zone="sql-release-savepoint">
 
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  <primary>RELEASE SAVEPOINT</primary>
 
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 </indexterm>
 
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 <indexterm zone="sql-release-savepoint">
 
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  <primary>savepoints</primary>
 
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  <secondary>releasing</secondary>
 
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 </indexterm>
 
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 <refsynopsisdiv>
 
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<synopsis>
 
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RELEASE [ SAVEPOINT ] <replaceable>savepoint_name</replaceable>
 
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</synopsis>
 
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 </refsynopsisdiv>
 
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 <refsect1>
 
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  <title>Description</title>
 
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  <para>
 
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   <command>RELEASE SAVEPOINT</command> destroys a savepoint previously defined
 
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   in the current transaction.
 
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  </para>
 
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  <para>
 
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   Destroying a savepoint makes it unavailable as a rollback point,
 
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   but it has no other user visible behavior.  It does not undo the
 
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   effects of commands executed after the savepoint was established.
 
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   (To do that, see <xref linkend="sql-rollback-to">.)
 
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   Destroying a savepoint when
 
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   it is no longer needed allows the system to reclaim some resources
 
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   earlier than transaction end.
 
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  </para>
 
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  <para>
 
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   <command>RELEASE SAVEPOINT</command> also destroys all savepoints that were
 
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   established after the named savepoint was established.
 
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  </para>
 
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 </refsect1>
 
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 <refsect1>
 
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  <title>Parameters</title>
 
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  <variablelist>
 
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   <varlistentry>
 
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    <term><replaceable>savepoint_name</replaceable></term>
 
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    <listitem>
 
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     <para>
 
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      The name of the savepoint to destroy.
 
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     </para>
 
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    </listitem>
 
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   </varlistentry>
 
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  </variablelist>
 
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 </refsect1>
 
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 <refsect1>
 
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  <title>Notes</title>
 
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  <para>
 
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   Specifying a savepoint name that was not previously defined is an error.
 
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  </para>
 
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  <para>
 
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   It is not possible to release a savepoint when the transaction is in
 
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   an aborted state.
 
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  </para>
 
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  <para>
 
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   If multiple savepoints have the same name, only the one that was most
 
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   recently defined is released.
 
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  </para>
 
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 </refsect1>
 
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 <refsect1>
 
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  <title>Examples</title>
 
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  <para>
 
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   To establish and later destroy a savepoint:
 
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<programlisting>
 
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BEGIN;
 
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    INSERT INTO table1 VALUES (3);
 
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    SAVEPOINT my_savepoint;
 
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    INSERT INTO table1 VALUES (4);
 
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    RELEASE SAVEPOINT my_savepoint;
 
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COMMIT;
 
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</programlisting>
 
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   The above transaction will insert both 3 and 4.
 
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  </para>
 
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 </refsect1>
 
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 <refsect1>
 
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  <title>Compatibility</title>
 
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  <para>
 
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   This command conforms to the <acronym>SQL</> standard.  The standard
 
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   specifies that the key word <literal>SAVEPOINT</literal> is
 
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   mandatory, but <productname>PostgreSQL</productname> allows it to
 
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   be omitted.
 
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  </para>
 
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 </refsect1>
 
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 <refsect1>
 
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  <title>See Also</title>
 
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  <simplelist type="inline">
 
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   <member><xref linkend="sql-begin"></member>
 
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   <member><xref linkend="sql-commit"></member>
 
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   <member><xref linkend="sql-rollback"></member>
 
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   <member><xref linkend="sql-rollback-to"></member>
 
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   <member><xref linkend="sql-savepoint"></member>
 
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  </simplelist>
 
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 </refsect1>
 
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</refentry>