"Suresh_" <suiyengar@yahoo.com> writes:
> I want to add an antijoin operator to PostgreSql.
I think you can already do what you want like this:
SELECT * FROM A FULL OUTER JOIN B ON (x=y)WHERE x IS NULL OR y IS NULL
So for example:
postgres=# select * from a;i
---12
(2 rows)
postgres=# select * from b;i
---23
(2 rows)
postgres=# select * from a full outer join b on (a.i=b.i) where a.i is null or b.i is null;i | i
---+---1 | | 3
(2 rows)
-- Gregory Stark EnterpriseDB http://www.enterprisedb.com