QUERY PLAN                          
--------------------------------------------------------------
 Seq Scan on tab1  (cost=0.00..39388.68 rows=1070 width=8)
   Filter: (SubPlan 1)
   SubPlan 1
     ->  Seq Scan on tab2  (cost=0.00..36.75 rows=11 width=4)
           Filter: (k = tab1.j)
(5 rows)