Subject | Re: [ib-support] Speed of Joins |
---|---|
Author | lele@seldati.it |
Post date | 2002-05-02T15:20:50Z |
>>>>> On Fri, 03 May 2002 00:39:03 +1000, Helen Borrie <helebor@...> said:HB> But, if you have an index on the column F, you can
HB> speed up that outer join (if it is what you need) by using the
HB> STARTING WITH predicate instead of LIKE. LIKE does not use an
HB> index, whereas STARTING WITH does.
Helen, I cannot test this right now, but are sure of this? Last time I
checked I seem to remember that FB was smart enough to recognize the
"something%" idiom, and optimize the plan to use an index if there is
one...
Anyway, surely STARTING WITH does use it.
bye, lele.
--
nickname: Lele Gaifax | Quando vivro' di quello che ho pensato ieri
real: Emanuele Gaifas | comincero' ad aver paura di chi mi copia.
email: lele@... | -- Fortunato Depero, 1929.