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diff --git a/doc/src/sgml/html/catalog-pg-enum.html b/doc/src/sgml/html/catalog-pg-enum.html new file mode 100644 index 0000000..504a1dd --- /dev/null +++ b/doc/src/sgml/html/catalog-pg-enum.html @@ -0,0 +1,49 @@ +<?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>53.20. pg_enum</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="catalog-pg-description.html" title="53.19. pg_description" /><link rel="next" href="catalog-pg-event-trigger.html" title="53.21. pg_event_trigger" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">53.20. <code class="structname">pg_enum</code></th></tr><tr><td width="10%" align="left"><a accesskey="p" href="catalog-pg-description.html" title="53.19. pg_description">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="catalogs.html" title="Chapter 53. System Catalogs">Up</a></td><th width="60%" align="center">Chapter 53. System Catalogs</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="catalog-pg-event-trigger.html" title="53.21. pg_event_trigger">Next</a></td></tr></table><hr /></div><div class="sect1" id="CATALOG-PG-ENUM"><div class="titlepage"><div><div><h2 class="title" style="clear: both">53.20. <code class="structname">pg_enum</code></h2></div></div></div><a id="id-1.10.4.22.2" class="indexterm"></a><p> + The <code class="structname">pg_enum</code> catalog contains entries + showing the values and labels for each enum type. The + internal representation of a given enum value is actually the OID + of its associated row in <code class="structname">pg_enum</code>. + </p><div class="table" id="id-1.10.4.22.4"><p class="title"><strong>Table 53.20. <code class="structname">pg_enum</code> Columns</strong></p><div class="table-contents"><table class="table" summary="pg_enum Columns" border="1"><colgroup><col /></colgroup><thead><tr><th class="catalog_table_entry"><p class="column_definition"> + Column Type + </p> + <p> + Description + </p></th></tr></thead><tbody><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">oid</code> <code class="type">oid</code> + </p> + <p> + Row identifier + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">enumtypid</code> <code class="type">oid</code> + (references <a class="link" href="catalog-pg-type.html" title="53.64. pg_type"><code class="structname">pg_type</code></a>.<code class="structfield">oid</code>) + </p> + <p> + The OID of the <a class="link" href="catalog-pg-type.html" title="53.64. pg_type"><code class="structname">pg_type</code></a> entry owning this enum value + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">enumsortorder</code> <code class="type">float4</code> + </p> + <p> + The sort position of this enum value within its enum type + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">enumlabel</code> <code class="type">name</code> + </p> + <p> + The textual label for this enum value + </p></td></tr></tbody></table></div></div><br class="table-break" /><p> + The OIDs for <code class="structname">pg_enum</code> rows follow a special + rule: even-numbered OIDs are guaranteed to be ordered in the same way + as the sort ordering of their enum type. That is, if two even OIDs + belong to the same enum type, the smaller OID must have the smaller + <code class="structfield">enumsortorder</code> value. Odd-numbered OID values + need bear no relationship to the sort order. This rule allows the + enum comparison routines to avoid catalog lookups in many common cases. + The routines that create and alter enum types attempt to assign even + OIDs to enum values whenever possible. + </p><p> + When an enum type is created, its members are assigned sort-order + positions 1..<em class="replaceable"><code>n</code></em>. But members added later might be given + negative or fractional values of <code class="structfield">enumsortorder</code>. + The only requirement on these values is that they be correctly + ordered and unique within each enum type. + </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="catalog-pg-description.html" title="53.19. pg_description">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="catalogs.html" title="Chapter 53. System Catalogs">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="catalog-pg-event-trigger.html" title="53.21. pg_event_trigger">Next</a></td></tr><tr><td width="40%" align="left" valign="top">53.19. <code class="structname">pg_description</code> </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.5 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 53.21. <code class="structname">pg_event_trigger</code></td></tr></table></div></body></html>
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