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| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 13:44:03 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 13:44:03 +0000 |
| commit | 293913568e6a7a86fd1479e1cff8e2ecb58d6568 (patch) | |
| tree | fc3b469a3ec5ab71b36ea97cc7aaddb838423a0c /doc/src/sgml/html/sql-release-savepoint.html | |
| parent | Initial commit. (diff) | |
| download | postgresql-16-293913568e6a7a86fd1479e1cff8e2ecb58d6568.tar.xz postgresql-16-293913568e6a7a86fd1479e1cff8e2ecb58d6568.zip | |
Adding upstream version 16.2.upstream/16.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'doc/src/sgml/html/sql-release-savepoint.html')
| -rw-r--r-- | doc/src/sgml/html/sql-release-savepoint.html | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/doc/src/sgml/html/sql-release-savepoint.html b/doc/src/sgml/html/sql-release-savepoint.html new file mode 100644 index 0000000..abb1169 --- /dev/null +++ b/doc/src/sgml/html/sql-release-savepoint.html @@ -0,0 +1,66 @@ +<?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>RELEASE 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-reindex.html" title="REINDEX" /><link rel="next" href="sql-reset.html" title="RESET" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">RELEASE SAVEPOINT</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-reindex.html" title="REINDEX">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 16.2 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-reset.html" title="RESET">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-RELEASE-SAVEPOINT"><div class="titlepage"></div><a id="id-1.9.3.164.1" class="indexterm"></a><a id="id-1.9.3.164.2" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">RELEASE SAVEPOINT</span></h2><p>RELEASE SAVEPOINT — release a previously defined savepoint</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis"> +RELEASE [ SAVEPOINT ] <em class="replaceable"><code>savepoint_name</code></em> +</pre></div><div class="refsect1" id="id-1.9.3.164.6"><h2>Description</h2><p> + <code class="command">RELEASE SAVEPOINT</code> releases the named savepoint and + all active savepoints that were created after the named savepoint, + and frees their resources. All changes made since the creation of + the savepoint that didn't already get rolled back are merged into + the transaction or savepoint that was active when the named savepoint + was created. Changes made after <code class="command">RELEASE SAVEPOINT</code> + will also be part of this active transaction or savepoint. + </p></div><div class="refsect1" id="id-1.9.3.164.7"><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 of the savepoint to release. + </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.164.8"><h2>Notes</h2><p> + Specifying a savepoint name that was not previously defined is an error. + </p><p> + It is not possible to release a savepoint when the transaction is in + an aborted state; to do that, use <a class="xref" href="sql-rollback-to.html" title="ROLLBACK TO SAVEPOINT"><span class="refentrytitle">ROLLBACK TO SAVEPOINT</span></a>. + </p><p> + If multiple savepoints have the same name, only the most recently defined + unreleased one is released. Repeated commands will release progressively + older savepoints. + </p></div><div class="refsect1" id="id-1.9.3.164.9"><h2>Examples</h2><p> + To establish and later release 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><p> + A more complex example with multiple nested subtransactions: +</p><pre class="programlisting"> +BEGIN; + INSERT INTO table1 VALUES (1); + SAVEPOINT sp1; + INSERT INTO table1 VALUES (2); + SAVEPOINT sp2; + INSERT INTO table1 VALUES (3); + RELEASE SAVEPOINT sp2; + INSERT INTO table1 VALUES (4))); -- generates an error +</pre><p> + In this example, the application requests the release of the savepoint + <code class="literal">sp2</code>, which inserted 3. This changes the insert's + transaction context to <code class="literal">sp1</code>. When the statement + attempting to insert value 4 generates an error, the insertion of 2 and + 4 are lost because they are in the same, now-rolled back savepoint, + and value 3 is in the same transaction context. The application can + now only choose one of these two commands, since all other commands + will be ignored: +</p><pre class="programlisting"> + ROLLBACK; + ROLLBACK TO SAVEPOINT sp1; +</pre><p> + Choosing <code class="command">ROLLBACK</code> will abort everything, including + value 1, whereas <code class="command">ROLLBACK TO SAVEPOINT sp1</code> will retain + value 1 and allow the transaction to continue. + </p></div><div class="refsect1" id="id-1.9.3.164.10"><h2>Compatibility</h2><p> + This command conforms to the <acronym class="acronym">SQL</acronym> standard. The standard + specifies that the key word <code class="literal">SAVEPOINT</code> is + mandatory, but <span class="productname">PostgreSQL</span> allows it to + be omitted. + </p></div><div class="refsect1" id="id-1.9.3.164.11"><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-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>, <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-reindex.html" title="REINDEX">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-reset.html" title="RESET">Next</a></td></tr><tr><td width="40%" align="left" valign="top">REINDEX </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.2 Documentation">Home</a></td><td width="40%" align="right" valign="top"> RESET</td></tr></table></div></body></html>
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