Find greatest in multiple groups across tables MySQL -

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i have table called packages contains data , related table contains other information. it's set this:

name|version|architecture|date|id

and in second table called distribution have this:

repo|id

the id's reference each other. want able newest (ordered date) grouping. want group name, architecture, , repo. problem can't seem normal greatest-n-in-group work right because have go across tables. have far

select     p1.name,     p1.version,     p1.arch,     d1.repo,     p1.date packages p1 inner join distribution d1     on p1.id = d1.id inner join (     select         name,         arch,         repo,         max(date) date     packages     inner join distribution         on packages.id = distribution.id     group         name,         arch,         repo ) sq     on p1.name = sq.name , p1.arch = sq.arch , d1.repo = sq.repo , p1.date = sq.date

the problem doesn't seem group repo correctly. doesn't give me unique repo.

edit: want newest version each repo. have max date in each repo, , groups.

edit 2: worked 1 answer bit this:

select p1.name, p1.version, p1.arch, d1.repo, p1.date packages p1 inner join     distribution d1     on p1.id = d1.id inner join (         select name, arch, repo, max(date) date         packages inner join distribution             on packages.id = distribution.id         group name, arch, repo     ) sq     on p1.name = sq.name , p1.arch = sq.arch , d1.repo = sq.repo , p1.date = sq.date

and seems working me.

i think want remove repo max query:

select p1.name, p1.version, p1.arch, d1.repo, p1.date packages p1 inner join      distribution d1      on p1.id = d1.id inner join      (select name, arch, max(date) date       packages       group name, arch      ) sq      on p1.name = sq.name , p1.arch = sq.arch , p1.date = sq.date;

edit:

if not repos have date, want filter distribution in subquery. however, still don't want put repo in aggregation:

select p1.name, p1.version, p1.arch, d1.repo, p1.date packages p1 inner join      distribution d1      on p1.id = d1.id inner join      (select name, arch, max(date) date       packages p join            distribution d            on p.id = d.id       group name, arch      ) sq      on p1.name = sq.name , p1.arch = sq.arch , p1.date = sq.date;

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