Re: [SOLVED] Query plan excluding index on view - Mailing list pgsql-performance

From Matt Klinker
Subject Re: [SOLVED] Query plan excluding index on view
Date
Msg-id 3bda20f60804070846w6e89fa2bg3676ef0d00d14fec@mail.gmail.com
Whole thread Raw
In response to Re: Query plan excluding index on view  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-performance
Removing the constants definitely did take care of the issue on 8.3 (still same query plan on 8.1).  Thanks for your help in getting this resolved, and sorry again for not including all relevant information on my initial request

On Fri, Apr 4, 2008 at 10:20 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
"Matt Klinker" <mklinker@gmail.com> writes:
> --Joined View:
> CREATE OR REPLACE VIEW directory_listing AS
>  SELECT school.id, school.name, school.description, 119075291 AS
> listing_type_fid
>    FROM school
> UNION ALL
>  SELECT company.id, company.name, company.description, 119074833 AS
> listing_type_fid
>    FROM company;

Ah, there's the problem :-(.  Can you get rid of the constants here?
The planner's currently not smart about UNION ALL subqueries unless
their SELECT lists contain just simple column references.

(Yes, fixing that is on the todo list, but don't hold your breath...
it'll be 8.4 material at the earliest.)

                       regards, tom lane

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