MySQL Many for Many table: getting number of results -

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i have database of 3 tables: users photos likes , basic outline so:

users: user_id name   photos: photo_id title url user_id  likes: user_id photo_id

what want enable user many photos , have photos liked many users.

obviously, want order these photos number of likes, can join , count()

what need can't figure out return number of 'likes' each photo has. how this?

my current sql is:

select    photos.photo_id,   photos.title,   photos.url,   users.name photos left outer join users on users.user_id = photos.user_id left outer join likes on likes.photo_id = photos.photo_id group likes.photo_id order count(*) desc limit 20

just add count(*) select list:

select    photos.photo_id,   photos.title,   photos.url,   users.name,   count(*) photos left outer join users on users.user_id = photos.user_id left outer join likes on likes.photo_id = photos.photo_id group likes.photo_id order count(*) desc limit 20

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