Andreas Kretschmer <akretschmer@xxxxxxxxxxxxx> writes: > Tom Lane <tgl@xxxxxxxxxxxxx> wrote: >> I see no bug here. Your second query asks for a much more complicated >> computation, it's not surprising it takes longer. > But sorry, I disagree. It is the same query with the same result. I can't see > how the queries should return different results. In the first query select id, avg(value) over (partition by value) from values where id = 50 order by id; the avg() calculations are being done over only rows with id = 50. In the second query select * from (select id, avg(value) over (partition by value) from values order by id) foo where id = 50; they are being done over all rows. In this particular example you happen to get the same result, but that's just because "avg(foo) over partition by foo" is a dumb example --- it will necessarily just yield identically foo. In more realistic computations the results would be different. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
