Hi, What is the meaning of 'materializing' a relation after sequential scan?
explain select * from tb1, tb2 where tb1.c1 = tb2.c2; QUERY PLAN ---------------------------------------------------------------- Nested Loop (cost=1.03..2.34 rows=3 width=24) Join Filter: (tb1.c1 = tb2.c1) -> Seq Scan on tb2 (cost=0.00..1.04 rows=4 width=12) -> Materialize (cost=1.03..1.06 rows=3 width=12) -> Seq Scan on tb1 (cost=0.00..1.03 rows=3 width=12) In this above plan, what does 'Material' mean? Thanks, Rupesh