I have a table in a Postgres DB where
col2 are foreign keys referring to the same column. I want only unique combinations of
(col1, col2), i.e. if
(1,2) is entered then
(2,1) should be rejected. How can I achieve that?
My table definition:
CREATE TABLE mytable ( id serial primary key, col1 int NOT NULL, col2 int NOT NULL, unique (col1, col2) )