The way we solved this was by not using a select statement after
the "IN". Using EXISTS instead of IN (Select...) significantly
speeds up all such queries.

thx for the input

--- In firebird-support@yahoogroups.com, "Adam" <s3057043@...> wrote:
>
> --- In firebird-support@yahoogroups.com, "callmefreud2" <rikki@>
wrote:
> >
> > We have a query that is fast in the FB 2.0 RC version, but in
2.0 and
> > 2.1 takes 20 minutes. Essentially it deletes all records from a
table
> > in a master detail relationship.
> > something like delete from detailTable where not exists (select
distict
> > masterTable.ID from masterTable where mastertableID =
detailTable.FK)
> >
> > Does anyone know what might have changed significantly after
that RC
> > version? And will it / can it be fixed.
>
> Should you not have a foreign key constraint on these fields? If
you
> did, it would be impossible for any such records to exist.
>
> Adam
>