mysql - Rails query selecting last record with distinct column -

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i need make query retrieve "last" records of distinct column.

i have model, languages, has 3 columns:

locale -> es | en | de version ->  1 | 2 | 3 data -> aaa | bbb | ccc

there can duplicated records locale, not version. example:

es | 1 | aaa es | 2 | aab es | 3 | aba en | 1 | bbb en | 2 | bab

and in example, need retrieve result:

es | 3 | aba en | 2 | bab

there last 2 versions of language. i'm doing query right now:

language.all.order('created_at desc').group(:locale)

but i'm getting:

es | 2 | aba en | 1 | bab

any ideas? in advance!

here raw mysql query give result set want:

select lang1.* languages lang1 inner join (     select l.locale, max(l.version) maxversion     languages l     group l.locale ) lang2 on lang1.locale = lang2.locale , lang1.version = lang2.maxversion

i not ruby person, as can offer. i'm hoping know how translate mysql query query language have in op.


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