Postgres Pro
Downloads
Home   >   mailing lists

possible optimizations - pushing filter before aggregation - Mailing list pgsql-hackers

From Pavel Stehule
Subject possible optimizations - pushing filter before aggregation
Date
Msg-id CAFj8pRAaL=j259JFSbCkVKcXzUJW0h1rNLjw0aOSgvta-B=zaw@mail.gmail.com
Whole thread Raw
Responses Re: possible optimizations - pushing filter before aggregation
List pgsql-hackers
Tree view
Hi

In one application I see slow queries. There is often used views like

CREATE VIEW v AS SELECT min(a) M1, min(b) M2,  max(c) M3, x, y, z
  FROM t1 GROUP BY x, y, z;

and queries like

SELECT * FROM v
  WHERE M2 = const1
        AND M3 > const2

Isn't possible in this case push equivalence before aggregation?

Regards

Pavel

pgsql-hackers by date:

Previous
From: Craig Ringer
Date:
Subject: Re: PATCH: Batch/pipelining support for libpq
Next
From: Dave Page
Date:
Subject: Re: Mail thread references in commits