11.03.2016 13:39, liviuslivius wrote:

>
> I see that in FB3 this was changed and before apply not null to column -
> all existed data are validated.

Correct.

> Is three some possibility to disable this behavior?

Nope.

> On my big table with 910 468 710 records this operation take 72 minutes.
> I am sure that all records contain value in this field and this check is
> then "useless".

But Firebird is not that sure. You may forget something and get
inconsistent database as a result.

Out of curiosity, how often do you change NULL <-> NOT NULL on such big
tables? ;-)


Dmitry