Sergi, What does ‘more effective query plan’ exactly means? Will the aggregation happen on the data nodes and why this flag set to ‘true’ leads to strange behavior described here [1] which sounds like a bug?
As for the documentation how would you rewrite existed setCollocated explanation [2] so that it becomes clearer what the flag is for and how it works? Please provide your doc version. [1] http://apache-ignite-users.70518.x6.nabble.com/NOT-IN-in-ignite-td9861.html [2] https://apacheignite.readme.io/docs/configuration-parameters#section--sqlfields-and-sqlfieldsquery-configuration-properties <https://apacheignite.readme.io/docs/configuration-parameters#section--sqlfields-and-sqlfieldsquery-configuration-properties> — Denis > On Jan 10, 2017, at 9:13 AM, Sergi Vladykin <sergi.vlady...@gmail.com> wrote: > > Yes, this flag indeed is very obscure. Basically it means that if you have > some query with aggregates (at the top level right now) and you know that > you will do GROUP BY by affinity key, then Ignite can generate a more > effective query plan with this flag set. > > Sergi > > 2017-01-10 2:22 GMT+03:00 Valentin Kulichenko <valentin.kuliche...@gmail.com >> : > >> Folks, >> >> One of the users faced an interesting case [1]. Basically, there is a >> query [2] which returns correct result when collocated flag is not set, but >> if it's true, several counts for each node is received by the client >> without being aggregated. Is this expected? I'm also attaching the test >> that reproduces behavior. >> >> Actually, the flag seems to be very confusing and documentation >> description [3] doesn't help a lot. I'm reading it and it's not clear what >> has to be collocated, what would happen if I incorrectly set the flag to >> true, etc. Probably, some examples could help. Can someone elaborate? >> >> [1] http://apache-ignite-users.70518.x6.nabble.com/NOT- >> IN-in-ignite-td9861.html >> [2] SELECT count(*) as COUNT FROM Person p join table(joinId VARCHAR(50) = >> ?) i on p.id = i.joinId >> [3] https://apacheignite.readme.io/docs/configuration- >> parameters#section--sqlfields-and-sqlfieldsquery-configuration-properties >> >> -Val >>
