> From: Carlos Macao
> I am planning to build a tool for inspecting Databases, looking for
> potencial situations, which lead to impossible GBak restore backup; like
> when NOT NULL fields include NULL values. It would be nice to have some
> feedback of known situations or links to related documents.

I wanted to create something similar last year, but did not have enough time.
Some notes:
- NOT NULL constraints
(can be defined at field level, or domain level)
- UNIQUE INDEXES/CONSTRAINTS
- PRIMARY/FOREIGN keys relationships
- check MAX values in RDB$FORMATS.RDB$FORMAT
(whether backup/restore is recommended)
- there probably should be possibility to force all SQL statements
to use NATURAL plan (in case indexes are corrupted)
- imho the only 100% check whether database is really restorable is to restore it.

Ivan
http://www.volny.cz/iprenosil/interbase