Re: how to tell if column set on update

Hello,

Le 20/07/09 15:19, chester c young a écrit :
> within a trigger need to know if the UPDATE statement set a column.  the column might be set to the old value or a
differentvalue.
 
> 
> (want to make sure the app is sending all necessary values)
> 
> thanks
> 

If the column to test is known -- e.g. column MyCol --, NEW.MyCol and
OLD.MyCol -- respectively value of MyCol after UPDATE and value of MyCol
before UPDATE -- can be compared.

I may be wrong if you are looking for the column(s) that are really
updated, not if such a column is updated or not. In this case, each
column of the target table may be tested with their respective new and
old values as well.

Regards.
--
nha / Lyon / France.