postgresql/doc/src/sgml/ref/rollback.sgml

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<!--
doc/src/sgml/ref/rollback.sgml
PostgreSQL documentation
-->
<refentry id="sql-rollback">
<indexterm zone="sql-rollback">
<primary>ROLLBACK</primary>
</indexterm>
<refmeta>
<refentrytitle>ROLLBACK</refentrytitle>
<manvolnum>7</manvolnum>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>ROLLBACK</refname>
<refpurpose>abort the current transaction</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
ROLLBACK [ WORK | TRANSACTION ] [ AND [ NO ] CHAIN ]
</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>
<indexterm zone="sql-rollback-chain">
<primary>chained transactions</primary>
</indexterm>
<variablelist>
<varlistentry>
<term><literal>WORK</literal></term>
<term><literal>TRANSACTION</literal></term>
<listitem>
<para>
Optional key words. They have no effect.
</para>
</listitem>
</varlistentry>
<varlistentry id="sql-rollback-chain">
<term><literal>AND CHAIN</literal></term>
<listitem>
<para>
If <literal>AND CHAIN</literal> is specified, a new transaction is
immediately started with the same transaction characteristics (see <xref
linkend="sql-set-transaction"/>) as the just finished one. Otherwise,
no new transaction is started.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para>
Use <xref linkend="sql-commit"/> to
successfully terminate a transaction.
</para>
<para>
Issuing <command>ROLLBACK</command> outside of a transaction
block emits a warning and otherwise has no effect. <command>ROLLBACK AND
CHAIN</command> outside of a transaction block is an error.
</para>
</refsect1>
<refsect1>
<title>Examples</title>
<para>
To abort all changes:
<programlisting>
ROLLBACK;
</programlisting></para>
</refsect1>
<refsect1>
<title>Compatibility</title>
<para>
The command <command>ROLLBACK</command> conforms to the SQL standard. The
form <literal>ROLLBACK TRANSACTION</literal> is a PostgreSQL extension.
</para>
</refsect1>
<refsect1>
<title>See Also</title>
<simplelist type="inline">
<member><xref linkend="sql-begin"/></member>
<member><xref linkend="sql-commit"/></member>
<member><xref linkend="sql-rollback-to"/></member>
</simplelist>
</refsect1>
</refentry>