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Green_GoodERP18_FSJ_Standard/PostgreSQL/doc/postgresql/html/sql-rollback-to.html

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  1. <?xml version="1.0" encoding="UTF-8" standalone="no"?>

  2. <!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 V1.79.1" /><link rel="prev" href="sql-rollback-prepared.html" title="ROLLBACK PREPARED" /><link rel="next" href="sql-savepoint.html" title="SAVEPOINT" /></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">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 12.4 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">

  3. ROLLBACK [ WORK | TRANSACTION ] TO [ SAVEPOINT ] <em class="replaceable"><code>savepoint_name</code></em>

  4. </pre></div><div class="refsect1" id="id-1.9.3.168.6"><h2>Description</h2><p>

  5.    Roll back all commands that were executed after the savepoint was

  6.    established.  The savepoint remains valid and can be rolled back to

  7.    again later, if needed.

  8.   </p><p>

  9.    <code class="command">ROLLBACK TO SAVEPOINT</code> implicitly destroys all savepoints that

  10.    were established after the named savepoint.

  11.   </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>

  12.       The savepoint to roll back to.

  13.      </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.168.8"><h2>Notes</h2><p>

  14.    Use <a class="xref" href="sql-release-savepoint.html" title="RELEASE SAVEPOINT"><span class="refentrytitle">RELEASE SAVEPOINT</span></a> to destroy a savepoint

  15.    without discarding the effects of commands executed after it was

  16.    established.

  17.   </p><p>

  18.    Specifying a savepoint name that has not been established is an error.

  19.   </p><p>

  20.    Cursors have somewhat non-transactional behavior with respect to

  21.    savepoints.  Any cursor that is opened inside a savepoint will be closed

  22.    when the savepoint is rolled back.  If a previously opened cursor is

  23.    affected by a <code class="command">FETCH</code> or <code class="command">MOVE</code> command inside a

  24.    savepoint that is later rolled back, the cursor remains at the

  25.    position that <code class="command">FETCH</code> left it pointing to (that is, the cursor

  26.    motion caused by <code class="command">FETCH</code> is not rolled back).

  27.    Closing a cursor is not undone by rolling back, either.

  28.    However, other side-effects caused by the cursor's query (such as

  29.    side-effects of volatile functions called by the query) <span class="emphasis"><em>are</em></span>

  30.    rolled back if they occur during a savepoint that is later rolled back.

  31.    A cursor whose execution causes a transaction to abort is put in a

  32.    cannot-execute state, so while the transaction can be restored using

  33.    <code class="command">ROLLBACK TO SAVEPOINT</code>, the cursor can no longer be used.

  34.   </p></div><div class="refsect1" id="id-1.9.3.168.9"><h2>Examples</h2><p>

  35.    To undo the effects of the commands executed after <code class="literal">my_savepoint</code>

  36.    was established:

  37. </p><pre class="programlisting">

  38. ROLLBACK TO SAVEPOINT my_savepoint;

  39. </pre><p>

  40.   </p><p>

  41.    Cursor positions are not affected by savepoint rollback:

  42. </p><pre class="programlisting">

  43. BEGIN;

  44. 

  45. DECLARE foo CURSOR FOR SELECT 1 UNION SELECT 2;

  46. 

  47. SAVEPOINT foo;

  48. 

  49. FETCH 1 FROM foo;

  50.  ?column? 

  51. ----------

  52.         1

  53. 

  54. ROLLBACK TO SAVEPOINT foo;

  55. 

  56. FETCH 1 FROM foo;

  57.  ?column? 

  58. ----------

  59.         2

  60. 

  61. COMMIT;

  62. </pre></div><div class="refsect1" id="id-1.9.3.168.10"><h2>Compatibility</h2><p>

  63.    The <acronym class="acronym">SQL</acronym> standard specifies that the key word

  64.    <code class="literal">SAVEPOINT</code> is mandatory, but <span class="productname">PostgreSQL</span>

  65.    and <span class="productname">Oracle</span> allow it to be omitted.  SQL allows

  66.    only <code class="literal">WORK</code>, not <code class="literal">TRANSACTION</code>, as a noise word

  67.    after <code class="literal">ROLLBACK</code>.  Also, SQL has an optional clause

  68.    <code class="literal">AND [ NO ] CHAIN</code> which is not currently supported by

  69.    <span class="productname">PostgreSQL</span>.  Otherwise, this command conforms to

  70.    the SQL standard.

  71.   </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 class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-rollback-prepared.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-savepoint.html">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">Home</a></td><td width="40%" align="right" valign="top"> SAVEPOINT</td></tr></table></div></body></html>
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