Subject Re: [firebird-support] What makes a database file size so big?
Author Alexey Kovyazin

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Database Analyst will give you an exact information of tables and indices sizes tab Tables -> sort on Size), their fragmentation due to versioning and blobs.
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Alexey Kovyazin


I use firebird 2.5 classic server on windows operating system.
Because our database file is quite big (18GB) and it starts to cause
(because of its size) some maintenance inconvenience we decided to try
to shrink it. After checking database statistics we deleted "useless"
records in tables that took the most space, we updated old useless blob
fields with null values. After backup and restore it turned out that new
database is only 3GB smaller than original. We checked the statistics
and according to results we have 2,3GB raw data in database file.
Restore only metadata creates database of 70MB size, restoring without
active indexes results with file 500MB smaller than original. I'm very
curious - so what makes our database file so big? Sum of clear metadata
and raw data is about 2,4GB, and what with other 12GB? Is anything we
can do to shrink our big database file (drop useless indexes or
something like that)?

Thank you in advance for your answer.

Best regards,
Małgorzata Barchańska

Małgorzata Barchańska

Fast Data Sp. z o.o.
Aleja Zwycięstwa 96/98, 81-451 Gdynia
Tel.: (58) 732 72 01
NIP : 5862214954,REGON : 220595046
KRS : 0000304310, Kapitał zakładowy 50 000 zł