simple trigger - beginner need help

From: <daud11_at_hotmail.com>
Date: Sat, 23 Jan 1999 04:04:24 GMT
Message-ID: <78bho3$60s$1@nnrp1.dejanews.com>

Hi

I am trying to create a trigger to automatically update column B after column A has been updated. For example, let say my table my-table has 2 cols colA and colB. I want whenever ColA is updated, colB get updated automatically but I am not sure how to write the trigger to do just that. I have tried using the code below but it still won't work.

create trigger tr_update
after update of colA on my-table
for each row
BEGIN

      update my-table set colB = <some calculation>
      where colA = :new.ColA;

END; I tried something like the above and I got an error saying table is mutating etc etc. I hope somebody can help me and I would also appreciate if a copy can be send to my hotmail address at daud11_at_hotmail.com

thank you
Daud11

-----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own Received on Fri Jan 22 1999 - 22:04:24 CST