I'm trying to create a seconds domain that is an interval 'mashed to seconds' as I once saw Tom describe it. decibel=# create domain rrs.seconds as double precision; CREATE DOMAIN decibel=# create cast (double precision as rrs.seconds) WITHOUT FUNCTION AS IMPLICIT; CREATE CAST decibel=# create function rrs.interval_to_seconds(interval) returns seconds as 'SELECT extract( EPOCH FROM $1 );' LANGUAGE SQL; CREATE FUNCTION decibel=# create cast (interval as rrs.seconds) WITH FUNCTION rrs.interval_to_seconds(interval) AS IMPLICIT; CREATE CAST decibel=# select cast('1 month'::interval AS seconds); ERROR: cannot cast type interval to seconds \dC shows that the cast is there, and rrs.interval_to_seconds works as expected, and according to \df does return seconds. Version is 7.4.5. -- Jim C. Nasby, Database Consultant decibel@xxxxxxxxxxx Give your computer some brain candy! www.distributed.net Team #1828 Windows: "Where do you want to go today?" Linux: "Where do you want to go tomorrow?" FreeBSD: "Are you guys coming, or what?" ---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives? http://archives.postgresql.org