with 3 models : user has_many posts / user has_many comments Using the new Active Record Query Interface , I am trying to write a query involving 2 counts in the select method : writing
@search = User.joins(:posts).select("*, users.id as user_id, COUNT(posts.id) as posted").uniq.group('users.id') generates the SQL : SELECT DISTINCT users.id as user_id, COUNT(posts.id) as posted FROM `users` INNER JOIN `posts` ON `posts`.`user_id` = `users`.`id` GROUP BY users.id; which is fine. I get user_id posted 1 9 2 1 3 3 4 14 5 17
I can also write a similar line to query the users.comments ( replacing posts by comments ... @search = User.joins(:comments).select("*, users.id as user_id, COUNT(comments.id) as commented").uniq.group('users.id') which generates the SQL: SELECT DISTINCT users.id as user_id, COUNT(comments.id) as commented FROM `users` INNER JOIN `comments` ON `comments`.`user_id` = `users`.`id` GROUP BY users.id; also correct, and I get user_id commented 1 42 2 40 3 40 4 32 5 30
I would like to have a single line to get both, posted and commented counts, but if I write : @search = User.joins(:posts, :comments).select("*, users.id as user_id, COUNT(posts.id) as posted, COUNT(comments.id) as commented").uniq.group('users.id') , this generates the SQL: SELECT DISTINCT users.id as user_id, COUNT(IF(comments.user_id = users.id, 1, NULL)) as commented FROM `users` INNER JOIN `comments` ON `comments`.`user_id` = `users`.`id` GROUP BY users.id; user_id posted commented and I get with : user_id posted commented 1 378 378 2 40 40 3 120 120 4 448 448 5 510 510
which is the combined number of records : posted * commented .... and not user_id posted commented 1 9 42 2 1 40 3 3 40 4 14 32 5 17 30
where am I wrong ? thanks for feedback