CALL
CALL
CALL - invoke a procedure
Synopsis
CALLname( [argument] [, ...] )
Description
CALL
executes a procedure.
If the procedure has any output parameters, then a result row will be returned, containing the values of those parameters.
Parameters
-
name -
The name (optionally schema-qualified) of the procedure.
-
argument -
An argument expression for the procedure call.
Arguments can include parameter names, using the syntax
name=>valueArguments must be supplied for all procedure parameters that lack defaults, including
OUTparameters. However, arguments matchingOUTparameters are not evaluated, so it's customary to just writeNULLfor them. (Writing something else for anOUTparameter might cause compatibility problems with future PostgreSQL versions.)
Notes
The user must have
EXECUTE
privilege on the procedure in
order to be allowed to invoke it.
To call a function (not a procedure), use
SELECT
instead.
If
CALL
is executed in a transaction block, then the
called procedure cannot execute transaction control statements.
Transaction control statements are only allowed if
CALL
is executed in its own transaction.
PL/pgSQL
handles output parameters
in
CALL
commands differently;
see
Section 41.6.3
.
Examples
CALL do_db_maintenance();
Compatibility
CALL
conforms to the SQL standard,
except for the handling of output parameters. The standard
says that users should write variables to receive the values
of output parameters.