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.\"     Title: CREATE TABLE AS
.\"    Author: The PostgreSQL Global Development Group
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: 2017-11-06
.\"    Manual: PostgreSQL 9.2.24 Documentation
.\"    Source: PostgreSQL 9.2.24
.\"  Language: English
.\"
.TH "CREATE TABLE AS" "7" "2017-11-06" "PostgreSQL 9.2.24" "PostgreSQL 9.2.24 Documentation"
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.SH "NAME"
CREATE_TABLE_AS \- define a new table from the results of a query
.\" CREATE TABLE AS
.SH "SYNOPSIS"
.sp
.nf
CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE \fItable_name\fR
    [ (\fIcolumn_name\fR [, \&.\&.\&.] ) ]
    [ WITH ( \fIstorage_parameter\fR [= \fIvalue\fR] [, \&.\&.\&. ] ) | WITH OIDS | WITHOUT OIDS ]
    [ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
    [ TABLESPACE \fItablespace_name\fR ]
    AS \fIquery\fR
    [ WITH [ NO ] DATA ]
.fi
.SH "DESCRIPTION"
.PP
\fBCREATE TABLE AS\fR
creates a table and fills it with data computed by a
\fBSELECT\fR
command\&. The table columns have the names and data types associated with the output columns of the
\fBSELECT\fR
(except that you can override the column names by giving an explicit list of new column names)\&.
.PP
\fBCREATE TABLE AS\fR
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
\fBSELECT\fR
statement whenever it is queried\&.
.SH "PARAMETERS"
.PP
GLOBAL or LOCAL
.RS 4
Ignored for compatibility\&. Use of these keywords is deprecated; refer to
CREATE TABLE (\fBCREATE_TABLE\fR(7))
for details\&.
.RE
.PP
TEMPORARY or TEMP
.RS 4
If specified, the table is created as a temporary table\&. Refer to
CREATE TABLE (\fBCREATE_TABLE\fR(7))
for details\&.
.RE
.PP
UNLOGGED
.RS 4
If specified, the table is created as an unlogged table\&. Refer to
CREATE TABLE (\fBCREATE_TABLE\fR(7))
for details\&.
.RE
.PP
\fItable_name\fR
.RS 4
The name (optionally schema\-qualified) of the table to be created\&.
.RE
.PP
\fIcolumn_name\fR
.RS 4
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\&.
.RE
.PP
WITH ( \fIstorage_parameter\fR [= \fIvalue\fR] [, \&.\&.\&. ] )
.RS 4
This clause specifies optional storage parameters for the new table; see
Storage Parameters
for more information\&. The
WITH
clause can also include
OIDS=TRUE
(or just
OIDS) to specify that rows of the new table should have OIDs (object identifiers) assigned to them, or
OIDS=FALSE
to specify that the rows should not have OIDs\&. See
CREATE TABLE (\fBCREATE_TABLE\fR(7))
for more information\&.
.RE
.PP
WITH OIDS, WITHOUT OIDS
.RS 4
These are obsolescent syntaxes equivalent to
WITH (OIDS)
and
WITH (OIDS=FALSE), respectively\&. If you wish to give both an
OIDS
setting and storage parameters, you must use the
WITH ( \&.\&.\&. )
syntax; see above\&.
.RE
.PP
ON COMMIT
.RS 4
The behavior of temporary tables at the end of a transaction block can be controlled using
ON COMMIT\&. The three options are:
.PP
PRESERVE ROWS
.RS 4
No special action is taken at the ends of transactions\&. This is the default behavior\&.
.RE
.PP
DELETE ROWS
.RS 4
All rows in the temporary table will be deleted at the end of each transaction block\&. Essentially, an automatic
\fBTRUNCATE\fR(7)
is done at each commit\&.
.RE
.PP
DROP
.RS 4
The temporary table will be dropped at the end of the current transaction block\&.
.RE
.RE
.PP
TABLESPACE \fItablespace_name\fR
.RS 4
The
\fItablespace_name\fR
is the name of the tablespace in which the new table is to be created\&. If not specified,
default_tablespace
is consulted, or
temp_tablespaces
if the table is temporary\&.
.RE
.PP
\fIquery\fR
.RS 4
A
\fBSELECT\fR(7),
TABLE, or
\fBVALUES\fR(7)
command, or an
\fBEXECUTE\fR(7)
command that runs a prepared
\fBSELECT\fR,
\fBTABLE\fR, or
\fBVALUES\fR
query\&.
.RE
.PP
WITH [ NO ] DATA
.RS 4
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\&.
.RE
.SH "NOTES"
.PP
This command is functionally similar to
SELECT INTO (\fBSELECT_INTO\fR(7)), but it is preferred since it is less likely to be confused with other uses of the
\fBSELECT INTO\fR
syntax\&. Furthermore,
\fBCREATE TABLE AS\fR
offers a superset of the functionality offered by
\fBSELECT INTO\fR\&.
.PP
Prior to
PostgreSQL
8\&.0,
\fBCREATE TABLE AS\fR
always included OIDs in the table it created\&. As of
PostgreSQL
8\&.0, the
\fBCREATE TABLE AS\fR
command allows the user to explicitly specify whether OIDs should be included\&. If the presence of OIDs is not explicitly specified, the
default_with_oids
configuration variable is used\&. As of
PostgreSQL
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
\fBCREATE TABLE AS\fR
should explicitly specify
WITH (OIDS)
to ensure desired behavior\&.
.SH "EXAMPLES"
.PP
Create a new table
films_recent
consisting of only recent entries from the table
films:
.sp
.if n \{\
.RS 4
.\}
.nf
CREATE TABLE films_recent AS
  SELECT * FROM films WHERE date_prod >= \*(Aq2002\-01\-01\*(Aq;
.fi
.if n \{\
.RE
.\}
.PP
To copy a table completely, the short form using the
TABLE
command can also be used:
.sp
.if n \{\
.RS 4
.\}
.nf
CREATE TABLE films2 AS
  TABLE films;
.fi
.if n \{\
.RE
.\}
.PP
Create a new temporary table
films_recent, consisting of only recent entries from the table
films, using a prepared statement\&. The new table has OIDs and will be dropped at commit:
.sp
.if n \{\
.RS 4
.\}
.nf
PREPARE recentfilms(date) AS
  SELECT * FROM films WHERE date_prod > $1;
CREATE TEMP TABLE films_recent WITH (OIDS) ON COMMIT DROP AS
  EXECUTE recentfilms(\*(Aq2002\-01\-01\*(Aq);
.fi
.if n \{\
.RE
.\}
.SH "COMPATIBILITY"
.PP
\fBCREATE TABLE AS\fR
conforms to the
SQL
standard\&. The following are nonstandard extensions:
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
The standard requires parentheses around the subquery clause; in
PostgreSQL, these parentheses are optional\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
In the standard, the
WITH [ NO ] DATA
clause is required; in PostgreSQL it is optional\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
PostgreSQL
handles temporary tables in a way rather different from the standard; see
CREATE TABLE (\fBCREATE_TABLE\fR(7))
for details\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
The
WITH
clause is a
PostgreSQL
extension; neither storage parameters nor OIDs are in the standard\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
The
PostgreSQL
concept of tablespaces is not part of the standard\&. Hence, the clause
TABLESPACE
is an extension\&.
.RE
.SH "SEE ALSO"
CREATE TABLE (\fBCREATE_TABLE\fR(7)), \fBEXECUTE\fR(7), \fBSELECT\fR(7), SELECT INTO (\fBSELECT_INTO\fR(7)), \fBVALUES\fR(7)