An index selection tool helps reduce costs in time and memory in selecting an index configuration or set of indexes for use by a database server in accessing a database in accordance with a workload of queries. The index selection tool attempts to reduce the number of indexes to be considered, the number...http://www.google.se/patents/US5913206?utm_source=gb-gplus-sharePatent US5913206 - Database system multi-column index selection for a workload
