17. An article of manufacture comprising a program storage medium readable by a computer and embodying one or more instructions executable by the computer to perform method steps for executing a query to retrieve data stored on a data storage device, the method comprising the step of: while accessing one or more indexes to retrieve row identifiers, applying index matching predicates in the query to select row identifiers; and applying index screening predicates to eliminate one or more selected row identifiers.
17. An article of manufacture comprising a program storage medium readable by a computer and embodying one or more instructions executable by the computer to perform method steps for executing a query to retrieve data stored on a data storage device, the method comprising the step of: while accessing one or more indexes to retrieve row identifiers, applying index matching predicates in the query to select row identifiers; and applying index screening predicates to eliminate one or more selected row identifiers. 18. The article of manufacture of claim 17, further comprising the step of identifying index matching predicates in the query.