CREATE TABLE ASSection: SQL Commands (7)Updated: 2003-11-02 |
CREATE TABLE ASSection: SQL Commands (7)Updated: 2003-11-02 |
CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } ] TABLE table_name [ (column_name [, ...] ) ]
AS query
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.
This command is functionally equivalent 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.
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.