I've experienced something similar once, but on Firebird 1.5 - probably 1.5.3 when first observed. I have no idea how or why it became slow, but in the end I created another table and filled it with data to get performance back. It was a static table basically containing population figures for each year, age and place - I think I normally filled it with population data once every year.

I cannot help you as to how to fix problems like this, just thought it could be nice for you to know that you're not the first person to observe something strange like this. Though my table just became a bit slower, maybe taking one or five minutes to count the 50000 records as opposed to subsecond or a few seconds on the other table with identical content.

Set

-----Original Message-----
From: firebird-support@yahoogroups.com [mailto:firebird-support@yahoogroups.com] On Behalf Of marrtins_dqdp
Sent: 12. september 2008 15:35
To: firebird-support@yahoogroups.com
Subject: [firebird-support] One table become very slow

Hello!

Firebird SS 2.1.1.17910-4
Windows XP Service pack 2
Filesize: ~800mb backup ~40mb

I noticed strage behaviour with one of my databases. Suddenly one
table (CLIENTS) become very slow to query. First it happened few weeks
ago - basic backup/restore helped (25 Aug). Today it happened again,
but now backup process also is going terribly slow.

Have not seen/hear about such beahviour in my more than 7 year
experience with first Interbase then Firebird.

I restarted all services - apache,firebird - nothing changed.
Restarted box - nothing changed.