Get all unique associations in Rails 5 -


i have , object rides , ride belongs_to company.

i list of rides

@rides = ride.where(...)

what need store companies of ride in @companies want have every company once, if 2 rides have same company.

you can unique companies of rides below:

@rides = ride.includes(:company).where(...)  @companies = @rides.map(&:company).uniq

note: includes load companies in single query associated resulting rides (prevents n+1 query problem).


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