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diff --git a/doc/src/sgml/html/view-pg-stats-ext.html b/doc/src/sgml/html/view-pg-stats-ext.html new file mode 100644 index 0000000..84f511a --- /dev/null +++ b/doc/src/sgml/html/view-pg-stats-ext.html @@ -0,0 +1,124 @@ +<?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>54.28. pg_stats_ext</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="view-pg-stats.html" title="54.27. pg_stats" /><link rel="next" href="view-pg-stats-ext-exprs.html" title="54.29. pg_stats_ext_exprs" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">54.28. <code class="structname">pg_stats_ext</code></th></tr><tr><td width="10%" align="left"><a accesskey="p" href="view-pg-stats.html" title="54.27. pg_stats">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="views.html" title="Chapter 54. System Views">Up</a></td><th width="60%" align="center">Chapter 54. System Views</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="view-pg-stats-ext-exprs.html" title="54.29. pg_stats_ext_exprs">Next</a></td></tr></table><hr /></div><div class="sect1" id="VIEW-PG-STATS-EXT"><div class="titlepage"><div><div><h2 class="title" style="clear: both">54.28. <code class="structname">pg_stats_ext</code> <a href="#VIEW-PG-STATS-EXT" class="id_link">#</a></h2></div></div></div><a id="id-1.10.5.32.2" class="indexterm"></a><p> + The view <code class="structname">pg_stats_ext</code> provides access to + information about each extended statistics object in the database, + combining information stored in the <a class="link" href="catalog-pg-statistic-ext.html" title="53.52. pg_statistic_ext"><code class="structname">pg_statistic_ext</code></a> + and <a class="link" href="catalog-pg-statistic-ext-data.html" title="53.53. pg_statistic_ext_data"><code class="structname">pg_statistic_ext_data</code></a> + catalogs. This view allows access only to rows of + <a class="link" href="catalog-pg-statistic-ext.html" title="53.52. pg_statistic_ext"><code class="structname">pg_statistic_ext</code></a> and <a class="link" href="catalog-pg-statistic-ext-data.html" title="53.53. pg_statistic_ext_data"><code class="structname">pg_statistic_ext_data</code></a> + that correspond to tables the user has permission to read, and therefore + it is safe to allow public read access to this view. + </p><p> + <code class="structname">pg_stats_ext</code> is also designed to present the + information in a more readable format than the underlying catalogs + — at the cost that its schema must be extended whenever new types + of extended statistics are added to <a class="link" href="catalog-pg-statistic-ext.html" title="53.52. pg_statistic_ext"><code class="structname">pg_statistic_ext</code></a>. + </p><div class="table" id="id-1.10.5.32.5"><p class="title"><strong>Table 54.28. <code class="structname">pg_stats_ext</code> Columns</strong></p><div class="table-contents"><table class="table" summary="pg_stats_ext 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">schemaname</code> <code class="type">name</code> + (references <a class="link" href="catalog-pg-namespace.html" title="53.32. pg_namespace"><code class="structname">pg_namespace</code></a>.<code class="structfield">nspname</code>) + </p> + <p> + Name of schema containing table + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">tablename</code> <code class="type">name</code> + (references <a class="link" href="catalog-pg-class.html" title="53.11. pg_class"><code class="structname">pg_class</code></a>.<code class="structfield">relname</code>) + </p> + <p> + Name of table + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">statistics_schemaname</code> <code class="type">name</code> + (references <a class="link" href="catalog-pg-namespace.html" title="53.32. pg_namespace"><code class="structname">pg_namespace</code></a>.<code class="structfield">nspname</code>) + </p> + <p> + Name of schema containing extended statistics object + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">statistics_name</code> <code class="type">name</code> + (references <a class="link" href="catalog-pg-statistic-ext.html" title="53.52. pg_statistic_ext"><code class="structname">pg_statistic_ext</code></a>.<code class="structfield">stxname</code>) + </p> + <p> + Name of extended statistics object + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">statistics_owner</code> <code class="type">name</code> + (references <a class="link" href="catalog-pg-authid.html" title="53.8. pg_authid"><code class="structname">pg_authid</code></a>.<code class="structfield">rolname</code>) + </p> + <p> + Owner of the extended statistics object + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">attnames</code> <code class="type">name[]</code> + (references <a class="link" href="catalog-pg-attribute.html" title="53.7. pg_attribute"><code class="structname">pg_attribute</code></a>.<code class="structfield">attname</code>) + </p> + <p> + Names of the columns included in the extended statistics object + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">exprs</code> <code class="type">text[]</code> + </p> + <p> + Expressions included in the extended statistics object + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">kinds</code> <code class="type">char[]</code> + </p> + <p> + Types of extended statistics object enabled for this record + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">inherited</code> <code class="type">bool</code> + (references <a class="link" href="catalog-pg-statistic-ext-data.html" title="53.53. pg_statistic_ext_data"><code class="structname">pg_statistic_ext_data</code></a>.<code class="structfield">stxdinherit</code>) + </p> + <p> + If true, the stats include values from child tables, not just the + values in the specified relation + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">n_distinct</code> <code class="type">pg_ndistinct</code> + </p> + <p> + N-distinct counts for combinations of column values. If greater + than zero, the estimated number of distinct values in the combination. + If less than zero, the negative of the number of distinct values divided + by the number of rows. + (The negated form is used when <code class="command">ANALYZE</code> believes that + the number of distinct values is likely to increase as the table grows; + the positive form is used when the column seems to have a fixed number + of possible values.) For example, -1 indicates a unique combination of + columns in which the number of distinct combinations is the same as the + number of rows. + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">dependencies</code> <code class="type">pg_dependencies</code> + </p> + <p> + Functional dependency statistics + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">most_common_vals</code> <code class="type">text[]</code> + </p> + <p> + A list of the most common combinations of values in the columns. + (Null if no combinations seem to be more common than any others.) + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">most_common_val_nulls</code> <code class="type">bool[]</code> + </p> + <p> + A list of NULL flags for the most common combinations of values. + (Null when <code class="structfield">most_common_vals</code> is.) + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">most_common_freqs</code> <code class="type">float8[]</code> + </p> + <p> + A list of the frequencies of the most common combinations, + i.e., number of occurrences of each divided by total number of rows. + (Null when <code class="structfield">most_common_vals</code> is.) + </p></td></tr><tr><td class="catalog_table_entry"><p class="column_definition"> + <code class="structfield">most_common_base_freqs</code> <code class="type">float8[]</code> + </p> + <p> + A list of the base frequencies of the most common combinations, + i.e., product of per-value frequencies. + (Null when <code class="structfield">most_common_vals</code> is.) + </p></td></tr></tbody></table></div></div><br class="table-break" /><p> + The maximum number of entries in the array fields can be controlled on a + column-by-column basis using the <a class="link" href="sql-altertable.html" title="ALTER TABLE"><code class="command">ALTER + TABLE SET STATISTICS</code></a> command, or globally by setting the + <a class="xref" href="runtime-config-query.html#GUC-DEFAULT-STATISTICS-TARGET">default_statistics_target</a> run-time parameter. + </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="view-pg-stats.html" title="54.27. pg_stats">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="views.html" title="Chapter 54. System Views">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="view-pg-stats-ext-exprs.html" title="54.29. pg_stats_ext_exprs">Next</a></td></tr><tr><td width="40%" align="left" valign="top">54.27. <code class="structname">pg_stats</code> </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"> 54.29. <code class="structname">pg_stats_ext_exprs</code></td></tr></table></div></body></html>
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