xenial (7) CREATE_TABLE_AS.7.gz

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 [, ...] ) ]
           [ WITH ( storage_parameter [= value] [, ... ] ) | WITH OIDS | 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.

       WITH ( storage_parameter [= value] [, ... ] )
           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 (CREATE_TABLE(7)) for more information.

       WITH OIDS
       WITHOUT OIDS
           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.

       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.

       The CREATE TABLE AS 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.

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 has OIDs and will be dropped at commit:

           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');

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; neither storage parameters nor OIDs are 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)