CREATE TABLE AS(7) PostgreSQL 15.7 Documentation CREATE TABLE AS(7)
NAME
CREATE_TABLE_AS - define a new table from the results of a query
SYNOPSIS
CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXISTS ] table_name
[ (column_name [, ...] ) ]
[ USING method ]
[ WITH ( storage_parameter [= value] [, ... ] ) | WITHOUT OIDS ]
[ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
[ TABLESPACE tablespace_name ]
AS query
[ WITH [ NO ] DATA ]
DESCRIPTION
CREATE TABLE AS creates a table and fills it with data computed by a
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.
CREATE TABLE AS requires CREATE privilege on the schema used for the
table.
PARAMETERS
GLOBAL or LOCAL
Ignored for compatibility. Use of these keywords is deprecated;
refer to CREATE TABLE (CREATE_TABLE(7)) for details.
TEMPORARY or TEMP
If specified, the table is created as a temporary table. Refer to
CREATE TABLE (CREATE_TABLE(7)) for details.
UNLOGGED
If specified, the table is created as an unlogged table. Refer to
CREATE TABLE (CREATE_TABLE(7)) for details.
IF NOT EXISTS
Do not throw an error if a relation with the same name already
exists; simply issue a notice and leave the table unmodified.
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.
USING method
This optional clause specifies the table access method to use to
store the contents for the new table; the method needs be an access
method of type TABLE. See Chapter 63 for more information. If this
option is not specified, the default table access method is chosen
for the new table. See default_table_access_method for more
information.
WITH ( storage_parameter [= value] [, ... ] )
This clause specifies optional storage parameters for the new
table; see Storage Parameters in the CREATE TABLE (CREATE_TABLE(7))
documentation for more information. For backward-compatibility the
WITH clause for a table can also include OIDS=FALSE to specify that
rows of the new table should contain no OIDs (object identifiers),
OIDS=TRUE is not supported anymore.
WITHOUT OIDS
This is backward-compatible syntax for declaring a table WITHOUT
OIDS, creating a table WITH OIDS is not supported anymore.
ON COMMIT
The behavior of temporary tables at the end of a transaction block
can be controlled using ON COMMIT. The three options are:
PRESERVE ROWS
No special action is taken at the ends of transactions. This is
the default behavior.
DELETE ROWS
All rows in the temporary table will be deleted at the end of
each transaction block. Essentially, an automatic TRUNCATE is
done at each commit.
DROP
The temporary table will be dropped at the end of the current
transaction block.
TABLESPACE tablespace_name
The tablespace_name 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.
query
A SELECT, TABLE, or VALUES command, or an EXECUTE command that runs
a prepared SELECT, TABLE, or VALUES query.
WITH [ NO ] DATA
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.
NOTES
This command is functionally similar to SELECT INTO (SELECT_INTO(7)),
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 offered by SELECT INTO.
EXAMPLES
Create a new table films_recent consisting of only recent entries from
the table films:
CREATE TABLE films_recent AS
SELECT * FROM films WHERE date_prod >= '2002-01-01';
To copy a table completely, the short form using the TABLE command can
also be used:
CREATE TABLE films2 AS
TABLE films;
Create a new temporary table films_recent, consisting of only recent
entries from the table films, using a prepared statement. The new table
will be dropped at commit:
PREPARE recentfilms(date) AS
SELECT * FROM films WHERE date_prod > $1;
CREATE TEMP TABLE films_recent ON COMMIT DROP AS
EXECUTE recentfilms('2002-01-01');
COMPATIBILITY
CREATE TABLE AS conforms to the SQL standard. The following are
nonstandard extensions:
• The standard requires parentheses around the subquery clause; in
PostgreSQL, these parentheses are optional.
• In the standard, the WITH [ NO ] DATA clause is required; in
PostgreSQL it is optional.
• PostgreSQL handles temporary tables in a way rather different from
the standard; see CREATE TABLE (CREATE_TABLE(7)) for details.
• The WITH clause is a PostgreSQL extension; storage parameters are
not in the standard.
• The PostgreSQL concept of tablespaces is not part of the standard.
Hence, the clause TABLESPACE is an extension.
SEE ALSO
CREATE MATERIALIZED VIEW (CREATE_MATERIALIZED_VIEW(7)), CREATE TABLE
(CREATE_TABLE(7)), EXECUTE(7), SELECT(7), SELECT INTO (SELECT_INTO(7)),
VALUES(7)
PostgreSQL 15.7 2024 CREATE TABLE AS(7)
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