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- <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>SAVEPOINT</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets V1.79.1" /><link rel="prev" href="sql-rollback-to.html" title="ROLLBACK TO SAVEPOINT" /><link rel="next" href="sql-security-label.html" title="SECURITY LABEL" /></head><body><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">SAVEPOINT</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-rollback-to.html" title="ROLLBACK TO SAVEPOINT">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 12.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-security-label.html" title="SECURITY LABEL">Next</a></td></tr></table><hr></hr></div><div class="refentry" id="SQL-SAVEPOINT"><div class="titlepage"></div><a id="id-1.9.3.169.1" class="indexterm"></a><a id="id-1.9.3.169.2" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">SAVEPOINT</span></h2><p>SAVEPOINT — define a new savepoint within the current transaction</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">
- SAVEPOINT <em class="replaceable"><code>savepoint_name</code></em>
- </pre></div><div class="refsect1" id="id-1.9.3.169.6"><h2>Description</h2><p>
- <code class="command">SAVEPOINT</code> establishes a new savepoint within
- the current transaction.
- </p><p>
- A savepoint is a special mark inside a transaction that allows all commands
- that are executed after it was established to be rolled back, restoring
- the transaction state to what it was at the time of the savepoint.
- </p></div><div class="refsect1" id="id-1.9.3.169.7"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="replaceable"><code>savepoint_name</code></em></span></dt><dd><p>
- The name to give to the new savepoint.
- </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.169.8"><h2>Notes</h2><p>
- Use <a class="xref" href="sql-rollback-to.html" title="ROLLBACK TO SAVEPOINT"><span class="refentrytitle">ROLLBACK TO SAVEPOINT</span></a> to
- rollback to a savepoint. Use <a class="xref" href="sql-release-savepoint.html" title="RELEASE SAVEPOINT"><span class="refentrytitle">RELEASE SAVEPOINT</span></a>
- to destroy a savepoint, keeping
- the effects of commands executed after it was established.
- </p><p>
- Savepoints can only be established when inside a transaction block.
- There can be multiple savepoints defined within a transaction.
- </p></div><div class="refsect1" id="id-1.9.3.169.9"><h2>Examples</h2><p>
- To establish a savepoint and later undo the effects of all commands executed
- after it was established:
- </p><pre class="programlisting">
- BEGIN;
- INSERT INTO table1 VALUES (1);
- SAVEPOINT my_savepoint;
- INSERT INTO table1 VALUES (2);
- ROLLBACK TO SAVEPOINT my_savepoint;
- INSERT INTO table1 VALUES (3);
- COMMIT;
- </pre><p>
- The above transaction will insert the values 1 and 3, but not 2.
- </p><p>
- To establish and later destroy a savepoint:
- </p><pre class="programlisting">
- BEGIN;
- INSERT INTO table1 VALUES (3);
- SAVEPOINT my_savepoint;
- INSERT INTO table1 VALUES (4);
- RELEASE SAVEPOINT my_savepoint;
- COMMIT;
- </pre><p>
- The above transaction will insert both 3 and 4.
- </p></div><div class="refsect1" id="id-1.9.3.169.10"><h2>Compatibility</h2><p>
- SQL requires a savepoint to be destroyed automatically when another
- savepoint with the same name is established. In
- <span class="productname">PostgreSQL</span>, the old savepoint is kept, though only the more
- recent one will be used when rolling back or releasing. (Releasing the
- newer savepoint with <code class="command">RELEASE SAVEPOINT</code> will cause the older one
- to again become accessible to <code class="command">ROLLBACK TO SAVEPOINT</code> and
- <code class="command">RELEASE SAVEPOINT</code>.) Otherwise, <code class="command">SAVEPOINT</code> is
- fully SQL conforming.
- </p></div><div class="refsect1" id="id-1.9.3.169.11"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-begin.html" title="BEGIN"><span class="refentrytitle">BEGIN</span></a>, <a class="xref" href="sql-commit.html" title="COMMIT"><span class="refentrytitle">COMMIT</span></a>, <a class="xref" href="sql-release-savepoint.html" title="RELEASE SAVEPOINT"><span class="refentrytitle">RELEASE SAVEPOINT</span></a>, <a class="xref" href="sql-rollback.html" title="ROLLBACK"><span class="refentrytitle">ROLLBACK</span></a>, <a class="xref" href="sql-rollback-to.html" title="ROLLBACK TO SAVEPOINT"><span class="refentrytitle">ROLLBACK TO SAVEPOINT</span></a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-rollback-to.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-security-label.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">ROLLBACK TO SAVEPOINT </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> SECURITY LABEL</td></tr></table></div></body></html>
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