When to use bitmap indexes

From: Philip Zubaly <zubaly_at_z-ware.com>
Date: 30 Nov 1998 22:22:02 GMT
Message-ID: <36631a8a$0$26846_at_mojo>

I understand that bitmap indexes are efficient for columns with a fairly small and static set of values, but am interested in gathering any information that I can on experience with them to help in decision making for a number of cases.

Several cases seem perfect candidates for bitmap indexes -- y/n columns which are often used in queries. But what about a column with 50 values and 100,000 records? What if values would be added every once in a while?

Is it all pretty much trial and error, or can the decision be quantified in any way?

thanks -- Received on Mon Nov 30 1998 - 23:22:02 CET