Turning Referential Integrity on/off

I wonder if there is a way of turning referential integrity on and off. create table cust_calls ( customer_num integer, call_dtime datetime year to minute, user_id char(18) default user, call_code char(1), call_descr char(240), res_dtime datetime year to minute, res_descr char(240), primary key (customer_num, call_dtime), foreign key (customer_num) references customer (customer_num), foreign key (call_code) references call_type (call_code) ); The foregn key statement defines the referential integrity but is there a way of defining it after the table has been created and/or droppping it once it has been defined. I'm in the process of defining a database and to much referetial integrity is an obstacle when trying to load the databas but handy during test and in a live environment. Orjan Lindberg Swedish EPA oli@environ.se