multi column query

["Sriram Dandapani" <sdandapani(at)counterpane(dot)com>]

Hi

When I update a table that has 20 columns and the where clause includes 16 of the columns (this is a data warehousing type update on aggregate fields),

The bitmap scan is not used by the optimizer. The table is indexed on 3 of the 20 fields. The update takes really long to finish (on a 6 million row table)

 

Do I need to do some “magic” with configuration to turn on bitmap scans.