--- In firebird-support@yahoogroups.com, Nick Upson <nick@u...> wrote:

> In article <d1eln8+m9s1@e...>, Diwic2 wrote:
> > But the question is: In what way does this select query write data

to

> > disk?
>
> A) it could trigger a sweep
>
> b) if a sort is required

Thanks for your answer, but...

The whole database is about 50 MB and the tables used in the select
statement are not many MB each. A sort would be easily done in memory,
and I don't see the plan suggesting a sort anyway.

That it would trigger a sweep seems to be highly improbable as the
sweep interval is set to 20000 and the "next transaction" value does
not move that much during the query's execution.

Any other ideas?

// David