Question

I want to build a rails request with 2 models.
I think it’s quite simple, but I don’t want to do a loop myself.

I’m in my country model:

  def self.find_for_user(user_id)
    wines = Wine.where("user_id = ?", user_id).group(:country_id)

    where("countries.id IN ?", wines.map())
  end

I want to get all countries depending the first request (the wines grouped by countries, I just need the countries)

I think I can do this in a single line where I put map() or another instruction. I just need to get all country_id fields for wines.

Thanks.

Answer 1

Assuming that you’ve got an association set up between wines and country (ie. has_many :wines in country.rb), I think this is what you’re looking for:

def self.find_for_user(user_id)
  joins(:wines).where('wines.user_id = ?', user_id).uniq
end