Hello, you can sum only interval type
create type x (a inteval); testdb011=> insert into x values ('1 day'::interval); INSERT 18871 1 testdb011=> insert into x values ('1 day'::interval); INSERT 18872 1 testdb011=> insert into x values ('1 day'::interval); INSERT 18873 1 testdb011=> insert into x values ('1 day'::interval); INSERT 18874 1 testdb011=> insert into x values ('1 day'::interval); INSERT 18875 1 testdb011=> insert into x values ('1 day'::interval); testdb011=> select sum(i) from x; sum -------- 6 days regards Pavel Stehule On Fri, 5 Mar 2004, arief# wrote: > Dear all, > > > I'm sorry if this sounds stupid or have been talked about before. > > Suppose I have a field in my table that's called duration with type > 'time without timezone'. How do I do sum on this field based on another > field let say called dateofevent? > > SQL: SELECT SUM(duration) FROM durtable GROUP BY dateofevent; > > gives me: > > ERROR: Unable to select an aggregate function sum(time without time > zone) > > Is this because of me still using PostgreSQL version 7.2.1 from Debian > Woody? Or some other stupidity? > > > TIA, Regards. > -arief > > > > > > > ---------------------------(end of broadcast)--------------------------- > TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED] > ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend