mysql select with joins and pivot table -


i have 4 tables: brands, category, brands_category, , files. brands , category linked brands_category has 2 columns: brand_id , category_id

## brands ## id  |  name |  url | ..  ## category ## id | name | order | ..  ## brands_category ## brand_id | category_id  ## files ## id | name | path | brand_id | uploaded_at

i want distinct brands of category , order uploaded_at files table without duplication of brands. have made quite few attempts cant results want. here success i've had:

select b.*, aa.uploaded_at      brands b    inner join   (select   bc.brand_id, f.uploaded_at                    brands_category bc                         inner join brands b                           on b.id = bc.brand_id                          inner join category c                           on c.id = bc.category_id                inner join files f                on f.brand_id = bc.brand_id                   c.id = 1                 group bc.brand_id order bc.brand_id desc, f.uploaded_at desc) aa        on b.id = aa.brand_id

i brands category of 1 latest uploaded_at date isn't being return when brand has multiple files associated it.

no need pivot table -- use standard joins:

select b.brand_id brands b     join brands_category bc on b.brand_id = bc.brand_id     join category c on bc.category_id = c.category_id     join files f on b.brand_id = f.brand_id c.category_name = 'some category' order f.uploaded_at

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