Subject UDF and null
Author Ann W. Harrison
In the long run, the right thing to do with UDF's is to
replace them (85% confidence). In the mean time, does
anyone have a suggestion for an alternate interface that
would allow passing nulls?

The original design (for those who haven't been here since
day 1) included three mechanisms for passing values between
InterBase and a UDF: value, reference, and descriptor. The
last actually passed a pointer to a structure that included
the datatype, length, scale, null status, and a pointer to
the actual data.

That mechanism allowed the very clever (ambitious? overly
eager? utterly insane?) programmer to write UDF's that were
data type independent. There has been no great clamor
for datatype independence from the user base, but there
is frequent complaint about the absence of null handling.



We have answers.