•Columns with
Low-to-Medium Cardinality
•‘Set-based’ manipulation of
data
•Especially good for
large, complex queries
–Orders of magnitude performance
improvement
•Fully integrated within
Oracle9i
–Created
and managed similar to other Oracle9i
indexes
–Used to
accelerate single-table access, joins, and aggregation
–Transparently
selected by the query optimizer
Bitmap indexes characteristics