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indexes w/ descending order

I have a reasonably large table (over 2 million rows) and my select results
need to be sorted in descending order. I've noticed, however, that my
queries ORDER'ed by DESC are at least twice as slow compared to sorting in
ascending order. Reason being, obviously, that MySQL only supports
ascending indexes.

Here's my questions:

a) are descending indexes planned for MySQL anytime soon? I notice the
CREATE INDEX syntax has a placeholder for specifying ASC or DESC, but it's
currently ignored. Do the latest alphas support this yet? This feature
would greatly improve the speed of my application.

b) Is there any tricks or tips to improve the speed of a descending ordered
select? Do different table types handle this differently?

Thanks in advance. :)
Talis
Jul 20 '05 #1
0 1672

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