rollback.sgml

PostgreSQL 8.1.4的源码 适用于Linux下的开源数据库系统

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$PostgreSQL: pgsql/doc/src/sgml/ref/rollback.sgml,v 1.18 2004/08/01 17:32:13 tgl Exp $
PostgreSQL documentation
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<refentry id="SQL-ROLLBACK">
 <refmeta>
  <refentrytitle id="SQL-ROLLBACK-TITLE">ROLLBACK</refentrytitle>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>ROLLBACK</refname>
  <refpurpose>abort the current transaction</refpurpose>
 </refnamediv>

 <indexterm zone="sql-rollback">
  <primary>ROLLBACK</primary>
 </indexterm>

 <refsynopsisdiv>
<synopsis>
ROLLBACK [ WORK | TRANSACTION ]
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <command>ROLLBACK</command> rolls back the current transaction and causes
   all the updates made by the transaction to be discarded.
  </para>
 </refsect1>

 <refsect1>
  <title>Parameters</title>

  <variablelist>
   <varlistentry>
    <term><literal>WORK</literal></term>
    <term><literal>TRANSACTION</literal></term>
    <listitem>
     <para>
      Optional key words. They have no effect.
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect1>

 <refsect1>
  <title>Notes</title>

  <para>
   Use <xref linkend="SQL-COMMIT" endterm="SQL-COMMIT-TITLE"> to
   successfully terminate a transaction.
  </para>

  <para>
   Issuing <command>ROLLBACK</> when not inside a transaction does
   no harm, but it will provoke a warning message.
  </para>
 </refsect1>

 <refsect1>
  <title>Examples</title>

  <para>
   To abort all changes:
<programlisting>
ROLLBACK;
</programlisting>
  </para>
 </refsect1>

 <refsect1>
  <title>Compatibility</title>

  <para>
   The SQL standard only specifies the two forms
   <literal>ROLLBACK</literal> and <literal>ROLLBACK
   WORK</literal>. Otherwise, this command is fully conforming.
  </para>
 </refsect1>

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

  <simplelist type="inline">
   <member><xref linkend="sql-begin" endterm="sql-begin-title"></member>
   <member><xref linkend="sql-commit" endterm="sql-commit-title"></member>
   <member><xref linkend="sql-rollback-to" endterm="sql-rollback-to-title"></member>
  </simplelist>
 </refsect1>
</refentry>

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