Are the indexes statistics up to date? Also, post the query, query plan, and indexes stats.
Carlos Firebird Performance in Detail - http://videos.firebirddevelopersday.com www.firebirdnews.org - www.FireBase.com.br ACacacfs> Hello, ACacacfs> In a select statement there are two tables joined by a single ACacacfs> matching field, with search conditions in both of them. One of them has ACacacfs> roughly 130000 records, while the other has 600. ACacacfs> Inspecting the plan generated by the optimizer, I realized that it ACacacfs> uses the shorter one as the controlling stream instead of the longer one ACacacfs> (i.e. the shorter table is at the left side). ACacacfs> Using a PLAN expression with the corresponding indexes to bypass ACacacfs> the plan deviced by the optimizer in order to switch the order of the ACacacfs> streams, the performance is boosted (nearly three times faster). ACacacfs> What can cause the optimizer to pick a shorter table as the ACacacfs> controlling stream ? ACacacfs> Is there a workaround to induce the optimizer to select the streams ACacacfs> in a fixed way or should I have to resort to a manually imposed PLAN ? ACacacfs> Thanks, ACacacfs> Aldo
