Re: How to deal with order by, group by, distinct for user-defined types

Ruey-Lung Hsiao <rlhsiao@gmail.com> writes:
>    My question is: how do I find or define ordering operators for my 
> user-defined type?

Create a default btree index operator class for the type.  See
http://developer.postgresql.org/docs/postgres/xindex.html
        regards, tom lane