Re: materialize - Mailing list pgsql-sql

From Tom Lane
Subject Re: materialize
Date
Msg-id 4140.1196114025@sss.pgh.pa.us
Whole thread Raw
In response to materialize  (Ehab Galal <ehabgalal123@hotmail.com>)
List pgsql-sql
Ehab Galal <ehabgalal123@hotmail.com> 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.
        regards, tom lane


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