Adrian Klaver <adrian.klaver@xxxxxxxxxxx> 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