Re: Query tuning experts: Any hope for tuning query with 5+ joins and a sort?

Sorry about the late reply.

I've been lecturing in the US, and haven't had much spare time for the newsgroup.

Remember that the optimizer is continually evolving, and it takes time for new features to spread through all the code areas. Depending on version, you will find that there are several places where special optimisation features don't work with new index options (viz function based, reverse key, descending column) indexes.

This is just one such example - it does work with 9.2 though.

--
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Jonathan Lewis
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william milbratz wrote in message ...



>1)  The /*+ ORDERED FIRST_ROWS */ hints work fine when I'm querying

on


>'normal' (i.e. btree indexes, nothing fancy...)..but when I used a

>function based index, Oracle doesn't take the hint..i.e. and does its

>own sorting. In addition, I've tried using the 'INDEX' and the

>'INDEX_ASC' hint. No avail.

>