Solution for a trigger

Question

Can anybody help me with this problem?
I have some works and I've put their ID and their HOURS in a Table. But some works are composed by another works (reflexive relation), so i've put a foreign key in the table related with the work which this row is composing (it can be NULL):
CREATE TABLE WORK (
id number(9) PRIMARY KEY,
HOURS number(4),
idBIG number(9),
FOREIGN KEY (idBIG) REFERENCES WORK(id) ON DELETE CASCADE);
This table doesn't cause problems but I want to put a trigger wich control when somebody update the HOURS of a work, updating the bigger one wich contains that work.
I've tried with this, but it doesn't work:
CREATE OR REPLACE TRIGGER COUNTINGHOURS
AFTER UPDATE ON WORK
FOR EACH ROW
WHEN (NEW.HOURS > 0)
begin
UPDATE WORK
SET horas = horas + :NEW.HOURS - :OLD.HOURS
WHERE id = :NEW.idBIG;
end COUNTINGHOURS;
RUN;
Anybody can help me...?
Thanks

Answer 1

Your solution won't work because the table WORK is mutating when you try to update WORK in your after-row-update-trigger. Use the standard solution to circumvent this problem, by collecting rowid's of the records being updated and moving the check from after-update-row to after-statement. Search for solutions for the mutating table problem. There are plenty of them.
Good luck,
Rob.