Today I faced with this question at: http://forums.oracle.com/forums/thread.jspa?messageID=9469239#9469239
========================================= The Question ================
I have a table having 5 million records.
If I want to build an index on one column,which index is better(bitmap or btree normal)?
The column had approx 6% different values for the total records in the table.
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My answer was:
With 5%, I’d go through btree,
bitmap have many detail that you should be aware.
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