I'm pretty sure you cannot change null/not null for a column, Duilio -
- certainly not for a table with existing records. What would it do
with NULL value fields if changed to NOT NULL?!

One solution would be to create a new column and pump the data across
to it (adding values where NULLs existed), then delete the old column.

Regards,
Andrew Ferguson
Andrew Ferguson
-- Shaking the nuts from the family tree.

--- In ib-support@y..., Duilio Foschi <dedalus@y...> wrote:
> reading the ALTER TABLE ALTER COLUMN command on the langref, I am
brought
> into thinking I can change the type of an existing column fron
nullable to
> not null.
>
> However, I cannot find no way to put this into practice.
>
> Any hint ?
>
> TIA
>
> Duilio Foschi