Christoph_Becker(at)t-online(dot)de (Christoph_Becker) writes:
> But the following simplification will produce the error:
> UPDATE p_behbl SET fallnr = p_kvk.lfdnr FROM p_kvk WHERE
> p_behbl.fallnr is null and p_behbl.patnr = p_kvk.patnr;
If there are multiple p_kvk rows matching some p_behbl row, then this
is a known problem. See the archives from a week or two back.
regards, tom lane