CREATE CONSTRAINT TRIGGER() SQL Commands CREATE CONSTRAINT TRIGGER()
NAME
CREATE CONSTRAINT TRIGGER - define a new constraint trigger
SYNOPSIS
CREATE CONSTRAINT TRIGGER name
AFTER event [ OR ... ]
ON table_name
[ FROM referenced_table_name ]
{ NOT DEFERRABLE | [ DEFERRABLE ] { INITIALLY IMMEDIATE | INITIALLY DEFERRED } }
FOR EACH ROW
EXECUTE PROCEDURE funcname ( arguments )
DESCRIPTION
CREATE CONSTRAINT TRIGGER creates a constraint trigger. This is the
same as a regular trigger except that the timing of the trigger firing
can be adjusted using SET CONSTRAINTS [set_constraints(l)]. Constraint
triggers must be AFTER ROW triggers. They can be fired either at the
end of the statement causing the triggering event, or at the end of the
containing transaction; in the latter case they are said to be
deferred. A pending deferred-trigger firing can also be forced to hap-
pen immediately by using SET CONSTRAINTS.
PARAMETERS
name The name of the constraint trigger. This is also the name to use
when modifying the trigger's behavior using SET CONSTRAINTS.
The name cannot be schema-qualified -- the trigger inherits the
schema of its table.
event One of INSERT, UPDATE, or DELETE; this specifies the event that
will fire the trigger. Multiple events can be specified using
OR.
table_name
The (possibly schema-qualified) name of the table in which the
triggering events occur.
referenced_table_name
The (possibly schema-qualified) name of another table referenced
by the constraint. This option is used for foreign-key con-
straints and is not recommended for general use.
DEFERRABLE
NOT DEFERRABLE
INITIALLY IMMEDIATE
INITIALLY DEFERRED
The default timing of the trigger. See the CREATE TABLE [cre-
ate_table(l)] documentation for details of these constraint
options.
funcname
The function to call when the trigger is fired. See CREATE TRIG-
GER [create_trigger(l)] for details.
arguments
Optional argument strings to pass to the trigger function. See
CREATE TRIGGER [create_trigger(l)] for details.
COMPATIBILITY
CREATE CONSTRAINT TRIGGER is a PostgreSQL extension of the SQL stan-
dard.
SEE ALSO
CREATE TRIGGER [create_trigger(l)], DROP TRIGGER [drop_trigger(l)], SET
CONSTRAINTS [set_constraints(l)]
SQL - Language Statements 2008-09-19 CREATE CONSTRAINT TRIGGER()
postgresql 8.3.4 - Generated Thu Oct 2 10:06:08 CDT 2008