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diff --git a/doc/src/sgml/html/sql-altercollation.html b/doc/src/sgml/html/sql-altercollation.html new file mode 100644 index 0000000..a8b8625 --- /dev/null +++ b/doc/src/sgml/html/sql-altercollation.html @@ -0,0 +1,98 @@ +<?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>ALTER COLLATION</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-alteraggregate.html" title="ALTER AGGREGATE" /><link rel="next" href="sql-alterconversion.html" title="ALTER CONVERSION" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">ALTER COLLATION</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-alteraggregate.html" title="ALTER AGGREGATE">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 15.4 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-alterconversion.html" title="ALTER CONVERSION">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-ALTERCOLLATION"><div class="titlepage"></div><a id="id-1.9.3.5.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">ALTER COLLATION</span></h2><p>ALTER COLLATION — change the definition of a collation</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis"> +ALTER COLLATION <em class="replaceable"><code>name</code></em> REFRESH VERSION + +ALTER COLLATION <em class="replaceable"><code>name</code></em> RENAME TO <em class="replaceable"><code>new_name</code></em> +ALTER COLLATION <em class="replaceable"><code>name</code></em> OWNER TO { <em class="replaceable"><code>new_owner</code></em> | CURRENT_ROLE | CURRENT_USER | SESSION_USER } +ALTER COLLATION <em class="replaceable"><code>name</code></em> SET SCHEMA <em class="replaceable"><code>new_schema</code></em> +</pre></div><div class="refsect1" id="id-1.9.3.5.5"><h2>Description</h2><p> + <code class="command">ALTER COLLATION</code> changes the definition of a + collation. + </p><p> + You must own the collation to use <code class="command">ALTER COLLATION</code>. + To alter the owner, you must also be a direct or indirect member of the new + owning role, and that role must have <code class="literal">CREATE</code> privilege on + the collation's schema. (These restrictions enforce that altering the + owner doesn't do anything you couldn't do by dropping and recreating the + collation. However, a superuser can alter ownership of any collation + anyway.) + </p></div><div class="refsect1" id="id-1.9.3.5.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="replaceable"><code>name</code></em></span></dt><dd><p> + The name (optionally schema-qualified) of an existing collation. + </p></dd><dt><span class="term"><em class="replaceable"><code>new_name</code></em></span></dt><dd><p> + The new name of the collation. + </p></dd><dt><span class="term"><em class="replaceable"><code>new_owner</code></em></span></dt><dd><p> + The new owner of the collation. + </p></dd><dt><span class="term"><em class="replaceable"><code>new_schema</code></em></span></dt><dd><p> + The new schema for the collation. + </p></dd><dt><span class="term"><code class="literal">REFRESH VERSION</code></span></dt><dd><p> + Update the collation's version. + See <a class="xref" href="sql-altercollation.html#SQL-ALTERCOLLATION-NOTES" title="Notes">Notes</a> below. + </p></dd></dl></div></div><div class="refsect1" id="SQL-ALTERCOLLATION-NOTES"><h2>Notes</h2><p> + When a collation object is created, the provider-specific version of the + collation is recorded in the system catalog. When the collation is used, + the current version is + checked against the recorded version, and a warning is issued when there is + a mismatch, for example: +</p><pre class="screen"> +WARNING: collation "xx-x-icu" has version mismatch +DETAIL: The collation in the database was created using version 1.2.3.4, but the operating system provides version 2.3.4.5. +HINT: Rebuild all objects affected by this collation and run ALTER COLLATION pg_catalog."xx-x-icu" REFRESH VERSION, or build PostgreSQL with the right library version. +</pre><p> + A change in collation definitions can lead to corrupt indexes and other + problems because the database system relies on stored objects having a + certain sort order. Generally, this should be avoided, but it can happen + in legitimate circumstances, such as when upgrading the operating system + to a new major version or when + using <code class="command">pg_upgrade</code> to upgrade to server binaries linked + with a newer version of ICU. When this happens, all objects depending on + the collation should be rebuilt, for example, + using <code class="command">REINDEX</code>. When that is done, the collation version + can be refreshed using the command <code class="literal">ALTER COLLATION ... REFRESH + VERSION</code>. This will update the system catalog to record the + current collation version and will make the warning go away. Note that this + does not actually check whether all affected objects have been rebuilt + correctly. + </p><p> + When using collations provided by <code class="literal">libc</code>, version + information is recorded on systems using the GNU C library (most Linux + systems), FreeBSD and Windows. When using collations provided by ICU, the + version information is provided by the ICU library and is available on all + platforms. + </p><div class="note"><h3 class="title">Note</h3><p> + When using the GNU C library for collations, the C library's version + is used as a proxy for the collation version. Many Linux distributions + change collation definitions only when upgrading the C library, but this + approach is imperfect as maintainers are free to back-port newer + collation definitions to older C library releases. + </p><p> + When using Windows for collations, version information is only available + for collations defined with BCP 47 language tags such as + <code class="literal">en-US</code>. + </p></div><p> + For the database default collation, there is an analogous command + <code class="literal">ALTER DATABASE ... REFRESH COLLATION VERSION</code>. + </p><p> + The following query can be used to identify all collations in the current + database that need to be refreshed and the objects that depend on them: +</p><pre class="programlisting"> +SELECT pg_describe_object(refclassid, refobjid, refobjsubid) AS "Collation", + pg_describe_object(classid, objid, objsubid) AS "Object" + FROM pg_depend d JOIN pg_collation c + ON refclassid = 'pg_collation'::regclass AND refobjid = c.oid + WHERE c.collversion <> pg_collation_actual_version(c.oid) + ORDER BY 1, 2; +</pre></div><div class="refsect1" id="id-1.9.3.5.8"><h2>Examples</h2><p> + To rename the collation <code class="literal">de_DE</code> to + <code class="literal">german</code>: +</p><pre class="programlisting"> +ALTER COLLATION "de_DE" RENAME TO german; +</pre><p> + </p><p> + To change the owner of the collation <code class="literal">en_US</code> to + <code class="literal">joe</code>: +</p><pre class="programlisting"> +ALTER COLLATION "en_US" OWNER TO joe; +</pre></div><div class="refsect1" id="id-1.9.3.5.9"><h2>Compatibility</h2><p> + There is no <code class="command">ALTER COLLATION</code> statement in the SQL + standard. + </p></div><div class="refsect1" id="id-1.9.3.5.10"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-createcollation.html" title="CREATE COLLATION"><span class="refentrytitle">CREATE COLLATION</span></a>, <a class="xref" href="sql-dropcollation.html" title="DROP COLLATION"><span class="refentrytitle">DROP COLLATION</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-alteraggregate.html" title="ALTER AGGREGATE">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-alterconversion.html" title="ALTER CONVERSION">Next</a></td></tr><tr><td width="40%" align="left" valign="top">ALTER AGGREGATE </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.4 Documentation">Home</a></td><td width="40%" align="right" valign="top"> ALTER CONVERSION</td></tr></table></div></body></html>
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