| CREATE_TABLE_AS(7) - phpMan
CREATE TABLE AS(7) PostgreSQL 12.3 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.
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. A notice is
issued in this case. Refer to CREATE TABLE (CREATE_TABLE(7)) 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.
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 60
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 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(7) 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(7), TABLE, or VALUES(7) command, or an EXECUTE(7) 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 12.3 2020 CREATE TABLE AS(7)
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