I confirmed this on Oracle: select last_value(id) over (order by id) as last_id, id from foo;
LAST_ID ID ------- -- 0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 So when you specify ORDER BY clause on window definition, the frame always contains rows preceding from current row, not only on aggregate. > > Doing a bit of poking around in the spec and the Oracle documentation, > I think (but I'm not 100% sure) that the results returned were correct > for the query: > > postgres=# select a, sum(a) over () from generate_series(1,10) a; > ERROR: either PARTITION BY or ORDER BY must be specified in window clause The empty window definition is forbidden temporarily because I didn't know how to take it although there's no problem to execute it. I haven't found any description on spec yet, I know at least Oracle allows it. I can find how to do it with the new (window execution model) design, (and the design is suitable to fix it above,) but at first before going into trivial specs, I would like core hackers to review the model is better than before or not. Thank you for your cooperation. Regards, -- Hitoshi Harada -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
