Re: How to notice column changes in trigger

Hello Christoph Haller ,

> >
> > >So you want the trigger executed only if assignments to b and/or c do

Do sime thing like this use if /then /esle s block for the problem

In the first if blick check that b and c is null by the declaration of
IS NULL after that you run the update command as required

The program code will show as

create function
CREATE FUNCTION BLAH_FUNCTION() RETURNS "trigger"
AS '
usual blah blah of declre and all ,

IF NEW.b IS NULL and NEW.C IS NULL THEN
ROCK BABY
ELSE
Do OTHERWISE
END IF;
more blah blah plpgsql';

CREATE TRIGGER BLAH
BEFORE UPDATE ON BLAH_TABLE
FOR EACH ROW
EXECUTE PROCEDURE BLAH_FUNCTION

Please revert back if this helps .

Regards
V Kashyap

> > >not appear within the update command. Right?
> > >
> >
> > Right, that's what I want.
> >
> I'm afraid I have no idea how to accomplish that.
>
> Regards, Christoph
>
>
>
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