Bitmap indexes and OLTP or alternatives?

I'm told bitmap indexes are not appropriate for an OLTP system because of their high update and insert costs. I have such a system but I'm looking for a way to optimize a query that I think they would help with, so I'm looking for alternatives. The problem is that as far as I know Oracle can't take advantage of multiple indexes on different columns unless they're bitmap indexes. Even then I'm not entirely sure how to have it do the right thing.

The query is something of the form

select * from tbl where a=:a and b=:b and c=:c

Where any of a,b,c might not be present for particular query. And I never know which of them is likely to be most selective. Specifically they are each soundex values from columns like "first name", "lastname", "address", etc.

The table in question takes a few thousand inserts per day as part of an OLTP system so latency matters, and lots of updates though not frequently on these columns. This is on 8.0.5, though I would be curious if 8i had (yet another) key feature that would help me.

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greg Received on Sun Nov 14 1999 - 17:26:34 CST