Re: Using quicksort for every external sort run - Mailing list pgsql-hackers

From Greg Stark
Subject Re: Using quicksort for every external sort run
Date
Msg-id CAM-w4HMXLUzL76Sy4r6MY7MyA32OcJ73wC1-A69aFRfZ3pFRBA@mail.gmail.com
Whole thread Raw
In response to Re: Using quicksort for every external sort run  (Peter Geoghegan <pg@heroku.com>)
List pgsql-hackers
On Sun, Apr 3, 2016 at 12:50 AM, Peter Geoghegan <pg@heroku.com> wrote:
> 1459308434.753 2016-03-30 05:27:14 CEST STATEMENT:  SELECT * FROM
> (SELECT a FROM int_test UNION SELECT a FROM int_test_padding OFFSET
> 1e10) ff;
>
> I think that this is invalid, because the query was intended as this:
>
> SELECT * FROM (SELECT * FROM (SELECT a FROM int_test UNION SELECT a
> FROM int_test_padding) gg OFFSET 1e10) ff;

ISTM OFFSET binds more loosely than UNION so these should be equivalent.


-- 
greg



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