Subject Re: [firebird-support] Sudden increase in execution times
Author Ann W. Harrison
PenWin wrote:
>> If you are deleting in one of the tables regularly, then you might
>> suffer from garbage collection at SELECT time, depending on the
>> architecture (SuperServer, ClassicServer) you use.
> There are no deletes on either of the tables. If hiding from the user is
> required, it is done by setting history.deleted to 1.

Ah. That's almost the same cost as a deletion - the old version of the
history record has to be garbage collected. If there's an index on the
deleted field in history, the index entry must also be removed. Since
there are likely to be LOTS of entries in that index with the same
the index deletion will be expensive ... less so in 2.0x than 1.5x.

Good luck,