Re: Hint to get this Query plan?

"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> writes:

> Given the normal size and speed of
> creation of bitmaps - if this query is
> important you could try creating a
> bitmap on (a,b).

But the "normal size" is dependent on it being a good candidate for bitmaps. If the cardinality of column a is low (in this case ~300) and the cardinality of b is low (in this case 4) it does not necessarily follow that the cardinality of (a,b) is low (~1200). In this case it might still be reasonable, but if b were another 300 then it wouldn't make any sense.

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greg Received on Tue Feb 08 2000 - 17:33:05 CST