Hello I am play with windows function. I was surprised so these queries has different results.
postgres=# select sum(a) over (partition by b), a, b from foo; sum | a | b -----+----+--- 19 | 1 | 1 19 | 1 | 1 19 | 2 | 1 19 | 4 | 1 19 | 2 | 1 19 | 4 | 1 19 | 5 | 1 93 | 11 | 3 93 | 12 | 3 93 | 22 | 3 93 | 16 | 3 93 | 16 | 3 93 | 16 | 3 (13 rows) postgres=# select sum(a) over (partition by b order by a), a, b from foo; sum | a | b -----+----+--- 2 | 1 | 1 2 | 1 | 1 6 | 2 | 1 6 | 2 | 1 14 | 4 | 1 14 | 4 | 1 19 | 5 | 1 11 | 11 | 3 23 | 12 | 3 71 | 16 | 3 71 | 16 | 3 71 | 16 | 3 93 | 22 | 3 (13 rows) I didn't expect so ORDER can change result of function sum. Please, can somebody explain it? regards Pavel Stehule -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
