Hello Dmitry,

>> Strangely, the issue is only present on firebird 2.1.2 and only when the event table has a very large number of records ~40 million. We have only tested the classic build and this only in a Linux (CentOS) environment. A backup and restore was not done between migrations between 2.1.1 and 2.1.2 - to my knowledge this is not required.
>
> While not being strictly required, this is usually recommended.
>
> Do you update the index statistics regularly, especially when the EVENT
> table goes from 10M to 40M records?
>
>> I only post here because a) I'm not entirely certain that this is a bug as such and b) I'm concerned that there may have been a change to the optimiser (which I cannot find in the release notes) that may have an impact on the speed of queries executed
>
> http://tracker.firebirdsql.org/browse/CORE-2078
> http://tracker.firebirdsql.org/browse/CORE-2411

As I'm currently in process of upgrading to 2.1.2, is there a more
general query pattern which applies to CORE-2411? The provided example
is, of course, rather specific for a particular query.

Thanks!


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Thomas Steinmaurer
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