Re: Auto incrementing key

Thank you Very much everyone who helpled me.

I could do my requirement with following trigger

CREATE OR REPLACE TRIGGER STUDENTID_T
   BEFORE INSERT
   ON student
   FOR EACH ROW
BEGIN
   IF (:NEW.student_id IS NULL) THEN

        SELECT CONCAT('s-',LPAD(CAST(id.NEXTVAL as char),8,'0')) INTO :NEW.student_Id FROM DUAL;

   END IF;
END But one more silly question. Can anyone tell me what is the meaning of 'from DUAL'
I used it without knowing. But like to know the meaning of it.

Thank you Received on Mon Apr 10 2006 - 03:48:39 CDT