activerecord - How to get ActiveRecord_Relation based on a ActiveRecord_Relation in rails? -


i have models user course

user.rb

has_many :courses

course.rb

belongs_to :user

if have activerecord_relation @users, list of user.

how activerecord_relation @courses, list of course based on @users

i know can done @users.each |user| 1 one. there easier way it? @users.courses?

you can use #flat_map method ruby:

@users.flat_map(&:courses)

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