Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com> writes:
> On 12/25/20 5:52 AM, Andreas Joseph Krogh wrote:
>> Or - is it possible to check for this in the trigger-function?
> As David Johnson mentioned you can check whether the value for the
> column is changed:
> NEW.animal <> OLD.animal
Better to use IS DISTINCT FROM, to get sane behavior when one or
the other value is NULL.
regards, tom lane