On Tue, 11 Mar 2008 08:27:05 +0530 "Robins Tharakan" <tharakan@xxxxxxxxx> wrote: > SELECT COUNT(*) from table WHERE indexed_field IS NULL > + > SELECT COUNT(*) from table WHERE indexed_field IS NOT NULL If the selectivity is appropriate yes. However if you have 1 million rows, and 200k of those rows are null (or not null), it is still going to seqscan. joshua d. drake -- The PostgreSQL Company since 1997: http://www.commandprompt.com/ PostgreSQL Community Conference: http://www.postgresqlconference.org/ Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate PostgreSQL SPI Liaison | SPI Director | PostgreSQL political pundit
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