> hum .. Thank a lot..
> I thought that is a basic functionally of
> relation database.

No database engine implements the same functionality.

If you check the SQL standard, you will see that not
every DDL action is defined. Adding or dropping
the NOT NULL constraint for a column isn't in the
standard either.

Would I like it for Firebird? I sure would.

> As i know as an "End User" we support not to change
> the internal "System table".

Very true, but with the "domain trick", you can do this
without modifying the system tables.

Martijn Tonies
Database Workbench - tool for InterBase, Firebird, MySQL, Oracle & MS SQL
Server
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