2009/10/16 Tom Lane <t...@sss.pgh.pa.us>: > Heikki Linnakangas <heikki.linnakan...@enterprisedb.com> writes: >> Andrey wrote: >>> select id, first_value(id) over(order by id), last_value(id) over(order by >>> id) from t; >>> >>> RESULT: >>> id | first_value | last_value >>> ----+-------------+------------ >>> 1 | 1 | 1 >>> 2 | 1 | 2 >>> 3 | 1 | 3 >>> (3 rows) >>> >>> fist_value - good, last_value - bad > >> Looks ok to me. What did you expect? > > These *are* the correct answers, since the default window frame runs > from first row to current row. If you don't like them, you may need > to specify a different window frame. > > regards, tom lane >
And it's well-documented. See http://www.postgresql.org/docs/8.4/static/functions-window.html -- Hitoshi Harada -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
