Question

I am trying to optimize my code with eager loading, but when ever where function is called, a query is executed in logs.

@votes_list = Vote.joins(:user => :profile).where(:post_id => post.id)
@male_votes = @votes_list.where(:profiles => { :gender => 1 }).count
@female_votes = @votes_list.where(:profiles => { :gender => 2 }).count

I am trying to make few queries after the first one, without need to fetch from database, how to do it?

Answer 1

You want to eagerly load the Users and their Profile for each vote. Then you can select the sub-set of votes in-memory broken down by gender on the profile.

@votes_list = Vote.where(:post_id => post.id, :include => { :user => :profile })
@male_votes = @votes_list.select {|v| v.user.profile.gender == 1}
@female_votes = @votes_list.select {|v| v.user.profile.gender == 2}