I need a certain unique constraint in pg that i can't figure out.
Given:
create table test_a (
id serial ,
name_1 varchar(32) ,
name_2 varchar(32)
);
I need name_1 and name_2 to both be unique so that:
name_1 never appears in name_1 or name_2
name_2 never appears in name_2 or name_1
a standard 2 column unique index / constraint will not accomplish this.