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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>CREATE TABLE AS</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-createtable.html" title="CREATE TABLE" /><link rel="next" href="sql-createtablespace.html" title="CREATE TABLESPACE" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">CREATE TABLE AS</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-createtable.html" title="CREATE TABLE">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 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-createtablespace.html" title="CREATE TABLESPACE">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-CREATETABLEAS"><div class="titlepage"></div><a id="id-1.9.3.86.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">CREATE TABLE AS</span></h2><p>CREATE TABLE AS — define a new table from the results of a query</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">3CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXISTS ] <em class="replaceable"><code>table_name</code></em>4 [ (<em class="replaceable"><code>column_name</code></em> [, ...] ) ]5 [ USING <em class="replaceable"><code>method</code></em> ]6 [ WITH ( <em class="replaceable"><code>storage_parameter</code></em> [= <em class="replaceable"><code>value</code></em>] [, ... ] ) | WITHOUT OIDS ]7 [ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]8 [ TABLESPACE <em class="replaceable"><code>tablespace_name</code></em> ]9 AS <em class="replaceable"><code>query</code></em>10 [ WITH [ NO ] DATA ]11</pre></div><div class="refsect1" id="id-1.9.3.86.5"><h2>Description</h2><p>12 <code class="command">CREATE TABLE AS</code> creates a table and fills it13 with data computed by a <code class="command">SELECT</code> command.14 The table columns have the15 names and data types associated with the output columns of the16 <code class="command">SELECT</code> (except that you can override the column17 names by giving an explicit list of new column names).18 </p><p>19 <code class="command">CREATE TABLE AS</code> bears some resemblance to20 creating a view, but it is really quite different: it creates a new21 table and evaluates the query just once to fill the new table22 initially. The new table will not track subsequent changes to the23 source tables of the query. In contrast, a view re-evaluates its24 defining <code class="command">SELECT</code> statement whenever it is25 queried.26 </p><p>27 <code class="command">CREATE TABLE AS</code> requires <code class="literal">CREATE</code>28 privilege on the schema used for the table.29 </p></div><div class="refsect1" id="id-1.9.3.86.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">GLOBAL</code> or <code class="literal">LOCAL</code></span></dt><dd><p>30 Ignored for compatibility. Use of these keywords is deprecated;31 refer to <a class="xref" href="sql-createtable.html" title="CREATE TABLE"><span class="refentrytitle">CREATE TABLE</span></a> for details.32 </p></dd></dl></div><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">TEMPORARY</code> or <code class="literal">TEMP</code></span></dt><dd><p>33 If specified, the table is created as a temporary table.34 Refer to <a class="xref" href="sql-createtable.html" title="CREATE TABLE"><span class="refentrytitle">CREATE TABLE</span></a> for details.35 </p></dd><dt><span class="term"><code class="literal">UNLOGGED</code></span></dt><dd><p>36 If specified, the table is created as an unlogged table.37 Refer to <a class="xref" href="sql-createtable.html" title="CREATE TABLE"><span class="refentrytitle">CREATE TABLE</span></a> for details.38 </p></dd><dt><span class="term"><code class="literal">IF NOT EXISTS</code></span></dt><dd><p>39 Do not throw an error if a relation with the same name already40 exists; simply issue a notice and leave the table unmodified.41 </p></dd><dt><span class="term"><em class="replaceable"><code>table_name</code></em></span></dt><dd><p>42 The name (optionally schema-qualified) of the table to be created.43 </p></dd><dt><span class="term"><em class="replaceable"><code>column_name</code></em></span></dt><dd><p>44 The name of a column in the new table. If column names are not45 provided, they are taken from the output column names of the query.46 </p></dd><dt><span class="term"><code class="literal">USING <em class="replaceable"><code>method</code></em></code></span></dt><dd><p>47 This optional clause specifies the table access method to use to store48 the contents for the new table; the method needs be an access method of49 type <code class="literal">TABLE</code>. See <a class="xref" href="tableam.html" title="Chapter 63. Table Access Method Interface Definition">Chapter 63</a> for more50 information. If this option is not specified, the default table access51 method is chosen for the new table. See <a class="xref" href="runtime-config-client.html#GUC-DEFAULT-TABLE-ACCESS-METHOD">default_table_access_method</a> for more information.52 </p></dd><dt><span class="term"><code class="literal">WITH ( <em class="replaceable"><code>storage_parameter</code></em> [= <em class="replaceable"><code>value</code></em>] [, ... ] )</code></span></dt><dd><p>53 This clause specifies optional storage parameters for the new table;54 see <a class="xref" href="sql-createtable.html#SQL-CREATETABLE-STORAGE-PARAMETERS" title="Storage Parameters">Storage Parameters</a> in the55 <a class="xref" href="sql-createtable.html" title="CREATE TABLE"><span class="refentrytitle">CREATE TABLE</span></a> documentation for more56 information. For backward-compatibility the <code class="literal">WITH</code>57 clause for a table can also include <code class="literal">OIDS=FALSE</code> to58 specify that rows of the new table should contain no OIDs (object59 identifiers), <code class="literal">OIDS=TRUE</code> is not supported anymore.60 </p></dd><dt><span class="term"><code class="literal">WITHOUT OIDS</code></span></dt><dd><p>61 This is backward-compatible syntax for declaring a table62 <code class="literal">WITHOUT OIDS</code>, creating a table <code class="literal">WITH63 OIDS</code> is not supported anymore.64 </p></dd><dt><span class="term"><code class="literal">ON COMMIT</code></span></dt><dd><p>65 The behavior of temporary tables at the end of a transaction66 block can be controlled using <code class="literal">ON COMMIT</code>.67 The three options are:68 69 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term"><code class="literal">PRESERVE ROWS</code></span></dt><dd><p>70 No special action is taken at the ends of transactions.71 This is the default behavior.72 </p></dd><dt><span class="term"><code class="literal">DELETE ROWS</code></span></dt><dd><p>73 All rows in the temporary table will be deleted at the end74 of each transaction block. Essentially, an automatic <a class="link" href="sql-truncate.html" title="TRUNCATE"><code class="command">TRUNCATE</code></a> is done75 at each commit.76 </p></dd><dt><span class="term"><code class="literal">DROP</code></span></dt><dd><p>77 The temporary table will be dropped at the end of the current78 transaction block.79 </p></dd></dl></div></dd><dt><span class="term"><code class="literal">TABLESPACE <em class="replaceable"><code>tablespace_name</code></em></code></span></dt><dd><p>80 The <em class="replaceable"><code>tablespace_name</code></em> is the name81 of the tablespace in which the new table is to be created.82 If not specified,83 <a class="xref" href="runtime-config-client.html#GUC-DEFAULT-TABLESPACE">default_tablespace</a> is consulted, or84 <a class="xref" href="runtime-config-client.html#GUC-TEMP-TABLESPACES">temp_tablespaces</a> if the table is temporary.85 </p></dd><dt><span class="term"><em class="replaceable"><code>query</code></em></span></dt><dd><p>86 A <a class="link" href="sql-select.html" title="SELECT"><code class="command">SELECT</code></a>, <a class="link" href="sql-select.html#SQL-TABLE" title="TABLE Command"><code class="command">TABLE</code></a>, or <a class="link" href="sql-values.html" title="VALUES"><code class="command">VALUES</code></a>87 command, or an <a class="link" href="sql-execute.html" title="EXECUTE"><code class="command">EXECUTE</code></a> command that runs a88 prepared <code class="command">SELECT</code>, <code class="command">TABLE</code>, or89 <code class="command">VALUES</code> query.90 </p></dd><dt><span class="term"><code class="literal">WITH [ NO ] DATA</code></span></dt><dd><p>91 This clause specifies whether or not the data produced by the query92 should be copied into the new table. If not, only the table structure93 is copied. The default is to copy the data.94 </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.86.7"><h2>Notes</h2><p>95 This command is functionally similar to <a class="xref" href="sql-selectinto.html" title="SELECT INTO"><span class="refentrytitle">SELECT INTO</span></a>, but it is96 preferred since it is less likely to be confused with other uses of97 the <code class="command">SELECT INTO</code> syntax. Furthermore, <code class="command">CREATE98 TABLE AS</code> offers a superset of the functionality offered99 by <code class="command">SELECT INTO</code>.100 </p></div><div class="refsect1" id="id-1.9.3.86.8"><h2>Examples</h2><p>101 Create a new table <code class="literal">films_recent</code> consisting of only102 recent entries from the table <code class="literal">films</code>:103 104</p><pre class="programlisting">105CREATE TABLE films_recent AS106 SELECT * FROM films WHERE date_prod >= '2002-01-01';107</pre><p>108 </p><p>109 To copy a table completely, the short form using110 the <code class="literal">TABLE</code> command can also be used:111 112</p><pre class="programlisting">113CREATE TABLE films2 AS114 TABLE films;115</pre><p>116 </p><p>117 Create a new temporary table <code class="literal">films_recent</code>, consisting of118 only recent entries from the table <code class="literal">films</code>, using a119 prepared statement. The new table will be dropped at commit:120 121</p><pre class="programlisting">122PREPARE recentfilms(date) AS123 SELECT * FROM films WHERE date_prod > $1;124CREATE TEMP TABLE films_recent ON COMMIT DROP AS125 EXECUTE recentfilms('2002-01-01');126</pre></div><div class="refsect1" id="id-1.9.3.86.9"><h2>Compatibility</h2><p>127 <code class="command">CREATE TABLE AS</code> conforms to the <acronym class="acronym">SQL</acronym>128 standard. The following are nonstandard extensions:129 130 </p><div class="itemizedlist"><ul class="itemizedlist compact" style="list-style-type: disc; "><li class="listitem"><p>131 The standard requires parentheses around the subquery clause; in132 <span class="productname">PostgreSQL</span>, these parentheses are133 optional.134 </p></li><li class="listitem"><p>135 In the standard, the <code class="literal">WITH [ NO ] DATA</code> clause136 is required; in PostgreSQL it is optional.137 </p></li><li class="listitem"><p><span class="productname">PostgreSQL</span> handles temporary tables in a way138 rather different from the standard; see139 <a class="xref" href="sql-createtable.html" title="CREATE TABLE"><span class="refentrytitle">CREATE TABLE</span></a>140 for details.141 </p></li><li class="listitem"><p>142 The <code class="literal">WITH</code> clause is a <span class="productname">PostgreSQL</span>143 extension; storage parameters are not in the standard.144 </p></li><li class="listitem"><p>145 The <span class="productname">PostgreSQL</span> concept of tablespaces is not146 part of the standard. Hence, the clause <code class="literal">TABLESPACE</code>147 is an extension.148 </p></li></ul></div></div><div class="refsect1" id="id-1.9.3.86.10"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-creatematerializedview.html" title="CREATE MATERIALIZED VIEW"><span class="refentrytitle">CREATE MATERIALIZED VIEW</span></a>, <a class="xref" href="sql-createtable.html" title="CREATE TABLE"><span class="refentrytitle">CREATE TABLE</span></a>, <a class="xref" href="sql-execute.html" title="EXECUTE"><span class="refentrytitle">EXECUTE</span></a>, <a class="xref" href="sql-select.html" title="SELECT"><span class="refentrytitle">SELECT</span></a>, <a class="xref" href="sql-selectinto.html" title="SELECT INTO"><span class="refentrytitle">SELECT INTO</span></a>, <a class="xref" href="sql-values.html" title="VALUES"><span class="refentrytitle">VALUES</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-createtable.html" title="CREATE TABLE">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-createtablespace.html" title="CREATE TABLESPACE">Next</a></td></tr><tr><td width="40%" align="left" valign="top">CREATE TABLE </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="40%" align="right" valign="top"> CREATE TABLESPACE</td></tr></table></div></body></html>