explain analyze SELECT Ma.User_Id, COUNT(*) COUNT FROM Manuim Ma WHERE Ma.Bb_Open_Date = (SELECT Bb_Open_Date FROM Manuim Man WHERE Man.User_Id = Ma.User_Id order by bb_open_date desc limit 1 ) GROUP BY Ma.User_Id HAVING COUNT(*) > 1;
QUERY PLAN ------------------------------------------------------------------------------------------------------------------------- ---------------------------------------- GroupAggregate (cost=0.56..2430770384.80 rows=128137 width=18) (actual time=55.823..2970443.757 rows=1213 loops=1) Group Key: ma.user_id Filter: (count(*) > 1) Rows Removed by Filter: 3693020 -> Index Scan using manuim_i_user_id on manuim ma (cost=0.56..2430767766.00 rows=178324 width=10) (actual time=0.249 ..2966355.734 rows=3695461 loops=1) Filter: (bb_open_date = (SubPlan 1)) Rows Removed by Filter: 31969367 SubPlan 1 -> Limit (cost=68.00..68.00 rows=1 width=8) (actual time=0.082..0.082 rows=0 loops=35664828) -> Sort (cost=68.00..68.04 rows=16 width=8) (actual time=0.081..0.081 rows=0 loops=35664828) Sort Key: man.bb_open_date DESC Sort Method: quicksort Memory: 25kB -> Index Scan using manuim_i_user_id on manuim man (cost=0.56..67.92 rows=16 width=8) (actual ti me=0.001..0.069 rows=85 loops=35664828) Index Cond: ((user_id)::text = (ma.user_id)::text) Planning time: 0.414 ms Execution time: 2970444.732 ms (16 rows) 2017-10-02 16:45 GMT+03:00 Gerardo Herzig <gher...@fmed.uba.ar>: > > > ----- Mensaje original ----- > > De: "Mariel Cherkassky" <mariel.cherkas...@gmail.com> > > Para: "Andreas Kretschmer" <andr...@a-kretschmer.de> > > CC: pgsql-performance@postgresql.org > > Enviados: Lunes, 2 de Octubre 2017 10:25:19 > > Asunto: Re: [PERFORM] select with max functions > > > > Andreas I tried to rewrite it with the function rank() but I failed. The > > query you wrote isnt the same as what I search. Moreover, I cant use > > explain analyze because it is taking to much time to run and I'm getting > > timeout.. > > > > 2017-10-01 21:48 GMT+03:00 Andreas Kretschmer <andr...@a-kretschmer.de>: > > Do a "set statement_timeout TO 0" prior to "explain analyze" >