Mark Steben <mark.steben@xxxxxxxxxxxxxxxxx> writes: > I would like to create an index on a column named value: defined as > varchar(255) > Values in this column can be many, including both dates and non-dates. > The developers run a query that first uses a regular expression to filter > non-dates out > then, ANDS it with the following > *and cast(value as date) >= date_trunc('MONTH', current_date) - interval ' > 2 Month '* > When I attempt to create an index using this statement in the > predicate, I get the error that states that functions in an index predicate > must be marked as Immutable. I think it's unhappy about the varchar-to-date cast. That is not considered immutable because the behavior of date_in() depends on the setting of DateStyle. regards, tom lane -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin