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diff --git a/doc/src/sgml/html/sql-rollback-to.html b/doc/src/sgml/html/sql-rollback-to.html new file mode 100644 index 0000000..c1281ba --- /dev/null +++ b/doc/src/sgml/html/sql-rollback-to.html @@ -0,0 +1,71 @@ +<?xml version="1.0" encoding="UTF-8" standalone="no"?> +<!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>ROLLBACK TO 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 Vsnapshot" /><link rel="prev" href="sql-rollback-prepared.html" title="ROLLBACK PREPARED" /><link rel="next" href="sql-savepoint.html" title="SAVEPOINT" /></head><body id="docContent" class="container-fluid col-10"><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">ROLLBACK TO SAVEPOINT</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-rollback-prepared.html" title="ROLLBACK PREPARED">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 14.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-savepoint.html" title="SAVEPOINT">Next</a></td></tr></table><hr></hr></div><div class="refentry" id="SQL-ROLLBACK-TO"><div class="titlepage"></div><a id="id-1.9.3.168.1" class="indexterm"></a><a id="id-1.9.3.168.2" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">ROLLBACK TO SAVEPOINT</span></h2><p>ROLLBACK TO SAVEPOINT — roll back to a savepoint</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis"> +ROLLBACK [ WORK | TRANSACTION ] TO [ SAVEPOINT ] <em class="replaceable"><code>savepoint_name</code></em> +</pre></div><div class="refsect1" id="id-1.9.3.168.6"><h2>Description</h2><p> + Roll back all commands that were executed after the savepoint was + established. The savepoint remains valid and can be rolled back to + again later, if needed. + </p><p> + <code class="command">ROLLBACK TO SAVEPOINT</code> implicitly destroys all savepoints that + were established after the named savepoint. + </p></div><div class="refsect1" id="id-1.9.3.168.7"><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 savepoint to roll back to. + </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.168.8"><h2>Notes</h2><p> + Use <a class="link" href="sql-release-savepoint.html" title="RELEASE SAVEPOINT"><code class="command">RELEASE SAVEPOINT</code></a> to destroy a savepoint + without discarding the effects of commands executed after it was + established. + </p><p> + Specifying a savepoint name that has not been established is an error. + </p><p> + Cursors have somewhat non-transactional behavior with respect to + savepoints. Any cursor that is opened inside a savepoint will be closed + when the savepoint is rolled back. If a previously opened cursor is + affected by a <code class="command">FETCH</code> or <code class="command">MOVE</code> command inside a + savepoint that is later rolled back, the cursor remains at the + position that <code class="command">FETCH</code> left it pointing to (that is, the cursor + motion caused by <code class="command">FETCH</code> is not rolled back). + Closing a cursor is not undone by rolling back, either. + However, other side-effects caused by the cursor's query (such as + side-effects of volatile functions called by the query) <span class="emphasis"><em>are</em></span> + rolled back if they occur during a savepoint that is later rolled back. + A cursor whose execution causes a transaction to abort is put in a + cannot-execute state, so while the transaction can be restored using + <code class="command">ROLLBACK TO SAVEPOINT</code>, the cursor can no longer be used. + </p></div><div class="refsect1" id="id-1.9.3.168.9"><h2>Examples</h2><p> + To undo the effects of the commands executed after <code class="literal">my_savepoint</code> + was established: +</p><pre class="programlisting"> +ROLLBACK TO SAVEPOINT my_savepoint; +</pre><p> + </p><p> + Cursor positions are not affected by savepoint rollback: +</p><pre class="programlisting"> +BEGIN; + +DECLARE foo CURSOR FOR SELECT 1 UNION SELECT 2; + +SAVEPOINT foo; + +FETCH 1 FROM foo; + ?column? +---------- + 1 + +ROLLBACK TO SAVEPOINT foo; + +FETCH 1 FROM foo; + ?column? +---------- + 2 + +COMMIT; +</pre></div><div class="refsect1" id="id-1.9.3.168.10"><h2>Compatibility</h2><p> + The <acronym class="acronym">SQL</acronym> standard specifies that the key word + <code class="literal">SAVEPOINT</code> is mandatory, but <span class="productname">PostgreSQL</span> + and <span class="productname">Oracle</span> allow it to be omitted. SQL allows + only <code class="literal">WORK</code>, not <code class="literal">TRANSACTION</code>, as a noise word + after <code class="literal">ROLLBACK</code>. Also, SQL has an optional clause + <code class="literal">AND [ NO ] CHAIN</code> which is not currently supported by + <span class="productname">PostgreSQL</span>. Otherwise, this command conforms to + the SQL standard. + </p></div><div class="refsect1" id="id-1.9.3.168.11"><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-savepoint.html" title="SAVEPOINT"><span class="refentrytitle">SAVEPOINT</span></a></span></div></div><div xmlns="http://www.w3.org/TR/xhtml1/transitional" class="navfooter"><hr></hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-rollback-prepared.html" title="ROLLBACK PREPARED">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-savepoint.html" title="SAVEPOINT">Next</a></td></tr><tr><td width="40%" align="left" valign="top">ROLLBACK PREPARED </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 14.5 Documentation">Home</a></td><td width="40%" align="right" valign="top"> SAVEPOINT</td></tr></table></div></body></html>
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