Alvaro Herrera <alvherre@xxxxxxxxxxxxxxxxx> writes: > You can't do this because to_date and other functions are not immutable. > 8.2 seems to be more picky about this -- the date conversions of > timestamptz columns are dependent on the current timezone. The reason 8.2 is more picky is that the function is less immutable thanks to the addition of locale-dependent functionality: http://archives.postgresql.org/pgsql-committers/2006-11/msg00264.php I gather that the underlying column is timestamp without tz, or it would never have worked in 8.1 either. That being the case, these index definitions seem pretty darn stupid anyway --- why aren't you just indexing on date_trunc or a plain cast to date? regards, tom lane
