>> But oracle accepts this one:
>> SQL> select * from re_eintraege where id='';
>> no rows selected
>> because oracle treats the empty string as NULL
>
>Oracle does that for string data, but it doesn't do it for numerics
>does it? In any case, that behavior is surely non-compliant with
>the SQL spec.
No, oracle accepts this and works correctly with number() datatype.
However I did not know that in postgres '' was treated as '0'.
Regards,
Mario Weilguni