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Actually, there is a worked example in my book which demonstrates that clustering and rows per index value is more important.
The actual example has 2,800 rows and a
cardinality of 560 (i.e. 5 rows per value).
Of course, the point up rate of change is
very important - bitmaps on tables
subject to almost any change tend
generate huge amounts of contention,
and fragment very badly.
-- Jonathan Lewis Yet another Oracle-related web site: http://www.jlcomp.demon.co.uk Practical Oracle 8i: Building Efficient Databases Publishers: Addison-Wesley Reviews at: http://www.jlcomp.demon.co.uk/book_rev.html Howard J. Rogers wrote in message <3a88e233_at_news.iprimus.com.au>...Received on Tue Feb 13 2001 - 01:40:13 CST
>But that aside, I believe there was a post ages ago (either from Jonathan
>Lewis or Steve Adams, but my brain may be failing me utterly, and it could
>have been someone completely different) that suggested a cardinality of 50
>is not unreasonable (it seems just a trifle high to me -I always teach a
>cardinality of 20 is where it starts to get dubious).