--- In ib-support@yahoogroups.com, "Thomas Steinmaurer" <ts@i...>
wrote:

> A table with one record.
>
> SQL> alter table mytable2 add myint3 integer not null;
> SQL> commit;
> SQL> select * from mytable2 where myint3 is null;
> I get a result set of one record <= wrong
> SQL> select * from mytable2 where myint3 is not null;
> I get an empty result set <= still wrong
> SQL> select * from mytable2 where myint3 = 0;
> I get an empty result set <= again wrong
> SQL> select * from mytable2;
> I get a result set of one record <= correct

Thomas, all results are correct except fact that you see '0' at
client representation when you must see 'null' if column defined as
Not Null. I'm not sure but seems null-flag of Not Null column is
wrongly cleared somewhere in chain engine-gds32. Internal queries and
gbak among them are not affected. And IIRC it was dependent on column
type too... Unfortunately I did'nt registered this bug myself, just
commented someone else's registration which was wrongly formulated and
can't quickly find it.

Best regards, Alexander.