Ignacio J. Ortega wrote:

> Hola a todos:
>
> Is there any way to detect if a field is a "not NULL" or "NULL" one by
> only using FB apis, without going to the rdb$* tables, and do a select
> in the system tables?
>

Have you looked at the XSQLVAR struct? Every column has an sqlind flag
which is set to -1 if the column is not null. The API guide discusses
this in more detail in the Chapter 'Working with Dynamic SQL' in the
section about SQL datatype macro constants.


Paul
--

Paul Reeves
http://www.ibphoenix.com
Supporting users of Firebird and InterBase