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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >CREATE TABLE AS</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REV="MADE" HREF="mailto:pgsql-docs@postgresql.org"><LINK REL="HOME" TITLE="PostgreSQL 9.2.24 Documentation" HREF="index.html"><LINK REL="UP" TITLE="SQL Commands" HREF="sql-commands.html"><LINK REL="PREVIOUS" TITLE="CREATE TABLE" HREF="sql-createtable.html"><LINK REL="NEXT" TITLE="CREATE TABLESPACE" HREF="sql-createtablespace.html"><LINK REL="STYLESHEET" TYPE="text/css" HREF="stylesheet.css"><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=ISO-8859-1"><META NAME="creation" CONTENT="2017-11-06T22:43:11"></HEAD ><BODY CLASS="REFENTRY" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="5" ALIGN="center" VALIGN="bottom" ><A HREF="index.html" >PostgreSQL 9.2.24 Documentation</A ></TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A TITLE="CREATE TABLE" HREF="sql-createtable.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="10%" ALIGN="left" VALIGN="top" ><A HREF="sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="60%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="20%" ALIGN="right" VALIGN="top" ><A TITLE="CREATE TABLESPACE" HREF="sql-createtablespace.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SQL-CREATETABLEAS" ></A >CREATE TABLE AS</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN71251" ></A ><H2 >Name</H2 >CREATE TABLE AS -- define a new table from the results of a query</DIV ><DIV CLASS="REFSYNOPSISDIV" ><A NAME="AEN71256" ></A ><H2 >Synopsis</H2 ><PRE CLASS="SYNOPSIS" >CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE <TT CLASS="REPLACEABLE" ><I >table_name</I ></TT > [ (<TT CLASS="REPLACEABLE" ><I >column_name</I ></TT > [, ...] ) ] [ WITH ( <TT CLASS="REPLACEABLE" ><I >storage_parameter</I ></TT > [= <TT CLASS="REPLACEABLE" ><I >value</I ></TT >] [, ... ] ) | WITH OIDS | WITHOUT OIDS ] [ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ] [ TABLESPACE <TT CLASS="REPLACEABLE" ><I >tablespace_name</I ></TT > ] AS <TT CLASS="REPLACEABLE" ><I >query</I ></TT > [ WITH [ NO ] DATA ]</PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN71264" ></A ><H2 >Description</H2 ><P > <TT CLASS="COMMAND" >CREATE TABLE AS</TT > creates a table and fills it with data computed by a <TT CLASS="COMMAND" >SELECT</TT > command. The table columns have the names and data types associated with the output columns of the <TT CLASS="COMMAND" >SELECT</TT > (except that you can override the column names by giving an explicit list of new column names). </P ><P > <TT CLASS="COMMAND" >CREATE TABLE AS</TT > bears some resemblance to creating a view, but it is really quite different: it creates a new table and evaluates the query just once to fill the new table initially. The new table will not track subsequent changes to the source tables of the query. In contrast, a view re-evaluates its defining <TT CLASS="COMMAND" >SELECT</TT > statement whenever it is queried. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN71273" ></A ><H2 >Parameters</H2 ><P ></P ><DIV CLASS="VARIABLELIST" ><DL ><DT ><TT CLASS="LITERAL" >GLOBAL</TT > or <TT CLASS="LITERAL" >LOCAL</TT ></DT ><DD ><P > Ignored for compatibility. Use of these keywords is deprecated; refer to <A HREF="sql-createtable.html" >CREATE TABLE</A > for details. </P ></DD ></DL ></DIV ><P ></P ><DIV CLASS="VARIABLELIST" ><DL ><DT ><TT CLASS="LITERAL" >TEMPORARY</TT > or <TT CLASS="LITERAL" >TEMP</TT ></DT ><DD ><P > If specified, the table is created as a temporary table. Refer to <A HREF="sql-createtable.html" >CREATE TABLE</A > for details. </P ></DD ><DT ><TT CLASS="LITERAL" >UNLOGGED</TT ></DT ><DD ><P > If specified, the table is created as an unlogged table. Refer to <A HREF="sql-createtable.html" >CREATE TABLE</A > for details. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >table_name</I ></TT ></DT ><DD ><P > The name (optionally schema-qualified) of the table to be created. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >column_name</I ></TT ></DT ><DD ><P > The name of a column in the new table. If column names are not provided, they are taken from the output column names of the query. </P ></DD ><DT ><TT CLASS="LITERAL" >WITH ( <TT CLASS="REPLACEABLE" ><I >storage_parameter</I ></TT > [= <TT CLASS="REPLACEABLE" ><I >value</I ></TT >] [, ... ] )</TT ></DT ><DD ><P > This clause specifies optional storage parameters for the new table; see <A HREF="sql-createtable.html#SQL-CREATETABLE-STORAGE-PARAMETERS" ><I >Storage Parameters</I ></A > for more information. The <TT CLASS="LITERAL" >WITH</TT > clause can also include <TT CLASS="LITERAL" >OIDS=TRUE</TT > (or just <TT CLASS="LITERAL" >OIDS</TT >) to specify that rows of the new table should have OIDs (object identifiers) assigned to them, or <TT CLASS="LITERAL" >OIDS=FALSE</TT > to specify that the rows should not have OIDs. See <A HREF="sql-createtable.html" >CREATE TABLE</A > for more information. </P ></DD ><DT ><TT CLASS="LITERAL" >WITH OIDS</TT ><BR><TT CLASS="LITERAL" >WITHOUT OIDS</TT ></DT ><DD ><P > These are obsolescent syntaxes equivalent to <TT CLASS="LITERAL" >WITH (OIDS)</TT > and <TT CLASS="LITERAL" >WITH (OIDS=FALSE)</TT >, respectively. If you wish to give both an <TT CLASS="LITERAL" >OIDS</TT > setting and storage parameters, you must use the <TT CLASS="LITERAL" >WITH ( ... )</TT > syntax; see above. </P ></DD ><DT ><TT CLASS="LITERAL" >ON COMMIT</TT ></DT ><DD ><P > The behavior of temporary tables at the end of a transaction block can be controlled using <TT CLASS="LITERAL" >ON COMMIT</TT >. The three options are: <P ></P ></P><DIV CLASS="VARIABLELIST" ><DL ><DT ><TT CLASS="LITERAL" >PRESERVE ROWS</TT ></DT ><DD ><P > No special action is taken at the ends of transactions. This is the default behavior. </P ></DD ><DT ><TT CLASS="LITERAL" >DELETE ROWS</TT ></DT ><DD ><P > All rows in the temporary table will be deleted at the end of each transaction block. Essentially, an automatic <A HREF="sql-truncate.html" >TRUNCATE</A > is done at each commit. </P ></DD ><DT ><TT CLASS="LITERAL" >DROP</TT ></DT ><DD ><P > The temporary table will be dropped at the end of the current transaction block. </P ></DD ></DL ></DIV ><P></P ></DD ><DT ><TT CLASS="LITERAL" >TABLESPACE <TT CLASS="REPLACEABLE" ><I >tablespace_name</I ></TT ></TT ></DT ><DD ><P > The <TT CLASS="REPLACEABLE" ><I >tablespace_name</I ></TT > is the name of the tablespace in which the new table is to be created. If not specified, <A HREF="runtime-config-client.html#GUC-DEFAULT-TABLESPACE" >default_tablespace</A > is consulted, or <A HREF="runtime-config-client.html#GUC-TEMP-TABLESPACES" >temp_tablespaces</A > if the table is temporary. </P ></DD ><DT ><TT CLASS="REPLACEABLE" ><I >query</I ></TT ></DT ><DD ><P > A <A HREF="sql-select.html" >SELECT</A >, <A HREF="sql-select.html#SQL-TABLE" >TABLE</A >, or <A HREF="sql-values.html" >VALUES</A > command, or an <A HREF="sql-execute.html" >EXECUTE</A > command that runs a prepared <TT CLASS="COMMAND" >SELECT</TT >, <TT CLASS="COMMAND" >TABLE</TT >, or <TT CLASS="COMMAND" >VALUES</TT > query. </P ></DD ><DT ><TT CLASS="LITERAL" >WITH [ NO ] DATA</TT ></DT ><DD ><P > This clause specifies whether or not the data produced by the query should be copied into the new table. If not, only the table structure is copied. The default is to copy the data. </P ></DD ></DL ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN71380" ></A ><H2 >Notes</H2 ><P > This command is functionally similar to <A HREF="sql-selectinto.html" >SELECT INTO</A >, but it is preferred since it is less likely to be confused with other uses of the <TT CLASS="COMMAND" >SELECT INTO</TT > syntax. Furthermore, <TT CLASS="COMMAND" >CREATE TABLE AS</TT > offers a superset of the functionality offered by <TT CLASS="COMMAND" >SELECT INTO</TT >. </P ><P > Prior to <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > 8.0, <TT CLASS="COMMAND" >CREATE TABLE AS</TT > always included OIDs in the table it created. As of <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > 8.0, the <TT CLASS="COMMAND" >CREATE TABLE AS</TT > command allows the user to explicitly specify whether OIDs should be included. If the presence of OIDs is not explicitly specified, the <A HREF="runtime-config-compatible.html#GUC-DEFAULT-WITH-OIDS" >default_with_oids</A > configuration variable is used. As of <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > 8.1, this variable is false by default, so the default behavior is not identical to pre-8.0 releases. Applications that require OIDs in the table created by <TT CLASS="COMMAND" >CREATE TABLE AS</TT > should explicitly specify <TT CLASS="LITERAL" >WITH (OIDS)</TT > to ensure desired behavior. </P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN71396" ></A ><H2 >Examples</H2 ><P > Create a new table <TT CLASS="LITERAL" >films_recent</TT > consisting of only recent entries from the table <TT CLASS="LITERAL" >films</TT >: </P><PRE CLASS="PROGRAMLISTING" >CREATE TABLE films_recent AS SELECT * FROM films WHERE date_prod >= '2002-01-01';</PRE ><P> </P ><P > To copy a table completely, the short form using the <TT CLASS="LITERAL" >TABLE</TT > command can also be used: </P><PRE CLASS="PROGRAMLISTING" >CREATE TABLE films2 AS TABLE films;</PRE ><P> </P ><P > Create a new temporary table <TT CLASS="LITERAL" >films_recent</TT >, consisting of only recent entries from the table <TT CLASS="LITERAL" >films</TT >, using a prepared statement. The new table has OIDs and will be dropped at commit: </P><PRE CLASS="PROGRAMLISTING" >PREPARE recentfilms(date) AS SELECT * FROM films WHERE date_prod > $1; CREATE TEMP TABLE films_recent WITH (OIDS) ON COMMIT DROP AS EXECUTE recentfilms('2002-01-01');</PRE ><P></P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN71409" ></A ><H2 >Compatibility</H2 ><P > <TT CLASS="COMMAND" >CREATE TABLE AS</TT > conforms to the <ACRONYM CLASS="ACRONYM" >SQL</ACRONYM > standard. The following are nonstandard extensions: <P ></P ></P><UL COMPACT="COMPACT" ><LI ><P > The standard requires parentheses around the subquery clause; in <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN >, these parentheses are optional. </P ></LI ><LI ><P > In the standard, the <TT CLASS="LITERAL" >WITH [ NO ] DATA</TT > clause is required; in PostgreSQL it is optional. </P ></LI ><LI ><P ><SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > handles temporary tables in a way rather different from the standard; see <A HREF="sql-createtable.html" >CREATE TABLE</A > for details. </P ></LI ><LI ><P > The <TT CLASS="LITERAL" >WITH</TT > clause is a <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > extension; neither storage parameters nor OIDs are in the standard. </P ></LI ><LI ><P > The <SPAN CLASS="PRODUCTNAME" >PostgreSQL</SPAN > concept of tablespaces is not part of the standard. Hence, the clause <TT CLASS="LITERAL" >TABLESPACE</TT > is an extension. </P ></LI ></UL ><P></P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN71433" ></A ><H2 >See Also</H2 ><A HREF="sql-createtable.html" >CREATE TABLE</A >, <A HREF="sql-execute.html" >EXECUTE</A >, <A HREF="sql-select.html" >SELECT</A >, <A HREF="sql-selectinto.html" >SELECT INTO</A >, <A HREF="sql-values.html" >VALUES</A ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="sql-createtable.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sql-createtablespace.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >CREATE TABLE</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="sql-commands.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >CREATE TABLESPACE</TD ></TR ></TABLE ></DIV ></BODY ></HTML >