the attachments are simple and small, just created for testing.

there are two table A and B. each table have two fields: A and B. Both
are varchar(10).
first, only A.A and B.A existed.
after insert some records, I add a new field B (not null). but the old
records, by default, the corresponding field (B) were still null.

question is why gbak cannot restore it because the not null constraint
exists.
So, what's the gbak philosophy?

BTW, the 2.fbk(see attachment) can be restored in interbase 7.1 without
any warning or error.

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