On Wed, 2002-08-14 at 13:09, Raymond Chui wrote:
> Let say I have a table has column1 and column2 and I made a trigger for
> after INSERT OR UPDATE for each row to execute procedure my_function.
>
> What I want is the trigger execute my_function only when column1 is
> insert or
> update, but not going to execute my_function when column2 is insert or
> update.
The trigger is executed unconditionally, so put the condition inside
my_function.
If it's an INSERT, column1 must be new, so:
IF TG_OP = ''INSERT'' OR
(TG_OP = ''UPDATE'' AND
(NEW.column1 != OLD.column1 OR
(NEW.column1 IS NULL AND OLD.column1 IS NOT NULL) OR
(NEW.column1 IS NOT NULL AND OLD.column1 IS NULL)
)
) THEN
...
END IF;
--
Oliver Elphick Oliver.Elphick@lfix.co.uk
Isle of Wight, UK
http://www.lfix.co.uk/oliver
GPG: 1024D/3E1D0C1C: CA12 09E0 E8D5 8870 5839 932A 614D 4C34 3E1D 0C1C
========================================
"For yourselves know perfectly that the day of the Lord
so cometh as a thief in the night. For when they shall
say, Peace and safety; then sudden destruction cometh
upon them, as travail upon a woman with child; and
they shall not escape." I Thessalonians 5:2,3
