2017-04-21 9:05 GMT+02:00 Marco Renzi <renzi....@gmail.com>: > > >> I am thinking so limit 10000 should be ok. Too big number can be messy >> for optimizer similarly like too small number. >> >> The planner is driven by statistics - and the statistics are not perfect >> - usually it is working on 80% - like weather forecasting. >> >> Usually it is working, but sometimes not. >> >> Regards >> >> Pavel >> >> >> > Thanks Pavel, i almost found two solutions at the end: > One is to use an inner limit as you said, and the other, when you just > know what the filter is, > is to try to join with SELECTS that have to be executed first from the > planner. > > Eg > SELECT fase.id > FROM tipofase > JOIN fase > ON (fase.tipofase = (SELECT tipofase.id FROM tipofase WHERE > tipofase.agendafrontoffice = true)) > > ORDER BY fase.id DESC limit 10 offset 0 > > Thanks for the help >
yes, sometimes when the data are not homogeneous more queries are necessary Regards Pavel > > -- > ------------------------------------------------------------ > ------------------------------------------------------------ > ------------------- > Ing. Marco Renzi > OCA - Oracle Certified Associate Java SE7 Programmer > OCP - Oracle Certified Mysql 5 Developer > > via Zegalara 57 > 62014 Corridonia(MC) > Mob: 3208377271 <(320)%20837-7271> > > > "The fastest way to change yourself is to hang out with people who are > already the way you want to be" Reid Hoffman >
