Subject | Re: [firebird-support] Indexes automatically used? |
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Author | Dmitry Yemanov |
Post date | 2005-08-15T12:12:55Z |
"Ivan Prenosil" <Ivan.Prenosil@...> wrote:
exact order.
performed instead. We don't support partially ORDER'ed retrievals.
Dmitry
>Yes, if this is a descending index which includes all columns above in their
> > Is the db "smart enough" to automatically use the composite index in the
> > case mentioned:
> >
> > Order by sort_order, empno, shiftdate, created desc
exact order.
> ORDER BY can use only one index.Correct.
> If you have separate indexes for each field, only one can be used (forIn fact, no indices can be used in this case, an external sort will be
> sort_order field).
performed instead. We don't support partially ORDER'ed retrievals.
Dmitry