Solved n+1 queries problem. #5
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Fixes: issue url
Fixed n+1 queries problem by adopting eager loading.
Changes
Added includes(:user) to make sure the associated user is loaded with score. Because it knows what user needs to be loaded beforehand, it can fetch all users of all requested scores in one query.
Before
(Lazy loading) A select user query is made for each score.
After
(Eager loading) Only one select query is needed to get users.