Thomas,

> You can't. Create a new field
>
> MY_NOTNULL_FIELD NUMERIC(5,2) DEFAULT 0 NOT NULL

Or use Database Workbench and simply edit the "not null" flag :-)

It does this by issueing a direct system table update -

update RDB$RELATION_FIELDS set
RDB$NULL_FLAG = 1
where (RDB$FIELD_NAME = 'MY_FIELD') and
(RDB$RELATION_NAME = 'MY_TABLE')




With regards,

Martijn Tonies
Database Workbench - the developer tool for InterBase & Firebird
Upscene Productions
http://www.upscene.com