Re: [SQL] materialize

2007-11-26 Thread Tom Lane
Ehab Galal <[EMAIL PROTECTED]> writes: > I was wondering why do we need the Materialize node in the plan below when i > explain a query? It's cheaper to scan a materialized rowset many times than a raw table --- we don't need to re-access shared memory nor re-check row visibility.

[SQL] materialize

2007-11-26 Thread Ehab Galal
Greetings, I was wondering why do we need the Materialize node in the plan below when i explain a query? 1: QUERY PLAN = "Nested Loop (cost=10.99..24.34 rows=1 width=846)"(typeid = 25, len = -1, typmod = -1, byval = f) 1: QUERY PLAN = " Join Filter: (("inner".cover)::text = ("