CREATE TABLE AS
SQL - Language Statements
CREATE TABLE AS
create a new table from the results of a query
CREATE TABLE AS
CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } ] TABLE table_name [ (column_name [, ...] ) ] [ [ WITH | WITHOUT ] OIDS ]
AS query
Description
CREATE TABLE AS creates a table and fills it
with data computed by a SELECT command or an
EXECUTE that runs a prepared
SELECT command. The table columns have the
names and data types associated with the output columns of the
SELECT (except that you can override the column
names by giving an explicit list of new column names).
CREATE TABLE AS 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 SELECT statement whenever it is
queried.
Parameters
GLOBAL or LOCAL
Ignored for compatibility. Refer to for
details.
TEMPORARY> or TEMP>
If specified, the table is created as a temporary table.
Refer to for details.
table_name
The name (optionally schema-qualified) of the table to be created.
column_name
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. If the table is created out of an
EXECUTE command, a column name list can
currently not be specified.
WITH OIDS
WITHOUT OIDS
This optional clause specifies whether the table created by
CREATE TABLE AS should include OIDs. If
neither form of this clause if specified, the value of the
configuration parameter is
used.
query
A query statement (that is, a SELECT command
or an EXECUTE command that runs a prepared
SELECT command). Refer to or ,
respectively, for a description of the allowed syntax.
Notes
This command is functionally similar to , but it is
preferred since it is less likely to be confused with other uses of
the SELECT INTO> syntax. Furthermore, CREATE
TABLE AS offers a superset of the functionality offerred
by SELECT INTO.
Prior to PostgreSQL 8.0, CREATE
TABLE AS always included OIDs in the table it
produced. Furthermore, these OIDs were newly generated: they were
distinct from the OIDs of any of the rows in the source tables of
the SELECT or EXECUTE
statement. Therefore, if CREATE TABLE AS was
frequently executed, the OID counter would be rapidly
incremented. As of PostgresSQL 8.0,
the CREATE TABLE AS command allows the user to
explicitely specify whether OIDs should be included. If the
presence of OIDs is not explicitely specified,
the configuration variable is
used. While this variable currently defaults to true, the default
value may be changed in the future. Therefore, applications that
require OIDs in the table created by CREATE TABLE
AS should explicitely specify WITH
OIDS to ensure compatibility with future versions
of PostgreSQL.
Compatibility
This command is modeled after an Oracle
feature. There is no command with equivalent functionality in
the SQL standard. However, a combination of CREATE
TABLE and INSERT ... SELECT can
accomplish the same thing with little more effort.
See Also