Re: Postgres 9.0 has a bias against indexes - Mailing list pgsql-performance

I even tried with an almost equivalent outer join:

 explain analyze select e1.empno,e1.ename,e2.empno,e2.ename
from emp e1 left outer join emp e2 on (e1.mgr=e2.empno);
                                                 QUERY PLAN

--------------------------------------------------------------------------------
------------------------------
 Nested Loop Left Join  (cost=0.00..7.25 rows=14 width=16) (actual time=0.028..0
.105 rows=14 loops=1)
  Join Filter: (e1.mgr = e2.empno)
  ->  Seq Scan on emp e1  (cost=0.00..2.14 rows=14 width=10) (actual time=0.006
..0.010 rows=14 loops=1)
  ->  Materialize  (cost=0.00..2.21 rows=14 width=8) (actual time=0.001..0.003
rows=14 loops=14)
        ->  Seq Scan on emp e2  (cost=0.00..2.14 rows=14 width=8) (actual time=
0.001..0.005 rows=14 loops=1)
 Total runtime: 0.142 ms
(6 rows)

This gives me the same result as the recursive version, minus the level column. I am porting an application from Oracle, there is a fairly large table that is accessed by "connect by". Rewriting it as a recursive join is not a problem, but the optimizer doesn't really use the indexes.