The attached fixes select_common_type() to support the below case:
create table t1( c1 int);
create domain dom_c1 int;
create table t2(c1 dom_c1);
select * from t1 join t2 using( c1 );
I didn't see a need for maintaining the domain as the preferred type. A
simple getBaseType() call on all elements of the list seems to be
enough.
--
Rod Taylor <rbt@rbt.ca>
PGP Key: http://www.rbt.ca/rbtpub.asc
