Re: Detecting changes to certain fields in 'before update' trigger functions

On Monday 01 December 2008 7:18:51 am Sebastian Tennant wrote:
> Hi list,
>
> First steps in trigger functions and PL/pgSQL so please bear with me...
>
> How can one detect changes to certain fields in before update trigger
> functions?
>
>  IF (NEW.<column-name> != OLD.<column-name>) THEN ...
>
> doesn't work, so obviously my understanding of the values of the
> varriables NEW and OLD in before update trigger functions is wrong; I
> had thought that OLD holds the record as it was before the update, and
> that NEW holds the record as it is since the update (but before the
> update has been committed)?
>
> How should one go about detecting changes to certain fields in before
> update trigger functions?
>
> Any help/advice much appreciated.
>
> Sebastian

It works here. Can you be more specific? Full function code, table schema,etc.


Thanks,
--
Adrian Klaver
aklaver@comcast.net