I'll start here because it's IB_SQL I am seeing the problem
in, but it's probably a Firebird niggle.

Have an older program that uses a UDF to do a MOD on a
number, and return the lower three numbers of a four number
staff ID. ( Fourth number is staff team )

Have switched to the .821 relase of Firebird for most
things, but these sites have still got 0.9.4 release.
When I try to use the MOD UDF in .821 build, I am getting an
'invalid column reference' error under some conditions.

SELECT APPLET
, INIT_ID AS STAFF
, MOD( INIT_ID, 1000 ) AS STAFF_ID
FROM TICKET

Works Fine

SELECT APPLET
, INIT_ID AS STAFF
, MOD( INIT_ID, 1000 ) AS STAFF_ID
FROM TICKET
GROUP BY APPLET, INIT_ID

Gives the error.

Anybody seen this sort of problem? We can quite happily live
with the older version of Firebird. It's been running almost
since it was released without a problem - unlike the
previous versions of Interbase. However I would like to look
at bringing this package upto the latest IBO, and at present
it will not even run on my new machine.

--
Lester Caine
-----------------------------
L.S.Caine Electronic Services