doc/src/sgml/ref/rollback.sgml

   1 <!--
   2 doc/src/sgml/ref/rollback.sgml
   3 PostgreSQL documentation
   4 -->
   5
   6 <refentry id="sql-rollback">
   7  <indexterm zone="sql-rollback">
   8   <primary>ROLLBACK</primary>
   9  </indexterm>
  10
  11  <refmeta>
  12   <refentrytitle>ROLLBACK</refentrytitle>
  13   <manvolnum>7</manvolnum>
  14   <refmiscinfo>SQL - Language Statements</refmiscinfo>
  15  </refmeta>
  16
  17  <refnamediv>
  18   <refname>ROLLBACK</refname>
  19   <refpurpose>abort the current transaction</refpurpose>
  20  </refnamediv>
  21
  22  <refsynopsisdiv>
  23 <synopsis>
  24 ROLLBACK [ WORK | TRANSACTION ] [ AND [ NO ] CHAIN ]
  25 </synopsis>
  26  </refsynopsisdiv>
  27
  28  <refsect1>
  29   <title>Description</title>
  30
  31   <para>
  32    <command>ROLLBACK</command> rolls back the current transaction and causes
  33    all the updates made by the transaction to be discarded.
  34   </para>
  35  </refsect1>
  36
  37  <refsect1>
  38   <title>Parameters</title>
  39
  40   <indexterm zone="sql-rollback-chain">
  41    <primary>chained transactions</primary>
  42   </indexterm>
  43
  44   <variablelist>
  45    <varlistentry id="sql-rollback-transaction">
  46     <term><literal>WORK</literal></term>
  47     <term><literal>TRANSACTION</literal></term>
  48     <listitem>
  49      <para>
  50       Optional key words. They have no effect.
  51      </para>
  52     </listitem>
  53    </varlistentry>
  54
  55    <varlistentry id="sql-rollback-chain">
  56     <term><literal>AND CHAIN</literal></term>
  57     <listitem>
  58      <para>
  59       If <literal>AND CHAIN</literal> is specified, a new (not aborted)
  60       transaction is immediately started with the same transaction
  61       characteristics (see <xref linkend="sql-set-transaction"/>) as the
  62       just finished one.  Otherwise, no new transaction is started.
  63      </para>
  64     </listitem>
  65    </varlistentry>
  66   </variablelist>
  67  </refsect1>
  68
  69  <refsect1>
  70   <title>Notes</title>
  71
  72   <para>
  73    Use <link linkend="sql-commit"><command>COMMIT</command></link> to
  74    successfully terminate a transaction.
  75   </para>
  76
  77   <para>
  78    Issuing <command>ROLLBACK</command> outside of a transaction
  79    block emits a warning and otherwise has no effect.  <command>ROLLBACK AND
  80    CHAIN</command> outside of a transaction block is an error.
  81   </para>
  82  </refsect1>
  83
  84  <refsect1>
  85   <title>Examples</title>
  86
  87   <para>
  88    To abort all changes:
  89 <programlisting>
  90 ROLLBACK;
  91 </programlisting></para>
  92  </refsect1>
  93
  94  <refsect1>
  95   <title>Compatibility</title>
  96
  97   <para>
  98    The command <command>ROLLBACK</command> conforms to the SQL standard.  The
  99    form <literal>ROLLBACK TRANSACTION</literal> is a PostgreSQL extension.
 100   </para>
 101  </refsect1>
 102
 103  <refsect1>
 104   <title>See Also</title>
 105
 106   <simplelist type="inline">
 107    <member><xref linkend="sql-begin"/></member>
 108    <member><xref linkend="sql-commit"/></member>
 109    <member><xref linkend="sql-rollback-to"/></member>
 110   </simplelist>
 111  </refsect1>
 112 </refentry>