Question

Have two triggers on a table. One trigger is executed when there is a insert or update for each row in the table. Second trigger is executed when there is a update for each row in the table. Which trigger gets executed first in ORACLE 10G when there is a update statement on a row in the table. Is there any order of execution for triggers in oracle? If so how can i set it?

Answer 1

The order in which the triggers will fire is arbitrary and not something that you can control in 10g. I believe, technically, it goes in the order that the triggers happened to be created but that’s certainly not something that you’d want to count on.

In 11g, you can control the firing order of triggers. However you are almost always better off replacing the two triggers with one trigger that calls two stored procedures. So rather than

CREATE TRIGGER trg_1
  BEFORE UPDATE ON t
  FOR EACH ROW
BEGIN
  <<do thing 1>>
END;


CREATE TRIGGER trg_2
  BEFORE UPDATE ON t
  FOR EACH ROW
BEGIN
  <<do thing 2>>
END;

you would be much better served with something like

CREATE PROCEDURE p1( <<arguments>> )
AS
BEGIN
  <<do thing 1>>
END;

CREATE PROCEDURE p2( <<arguments>> )
AS
BEGIN
  <<do thing 2>>
END;

CREATE TRIGGER trg
  BEFORE UPDATE ON t
  FOR EACH ROW
BEGIN
  p1( <<list of arguments>> );
  p2( <<list of arguments>> );
END;