ruby on rails - Using multiple has_many associations on one model -

i working in rails app company has_many orders. order has name , it. order can have_many television_spots, radio_placements, , newspaper_placements, data in these tables not same have split up. if order has_many radio_placements not have television_spots or newspaper_placements. question bad practice have has_many relationship on model if not exist?, better better make company have_many television_orders , television_order have_many television_spots? , company have_many radio_orders , radio_order have_many radio_placements, , on. think first option dryer using second strategy result in cleaner more understandable code app grows , data changes.

it's not bad practice have has_many association not have models associated. real question object type radio_placements, television_spots , newspaper_placements should associated to. if should in fact related order model, place associations there. understanding of question/data shape appear want these relationships on order model. like:

class company     has_many :orders     has_many :television_spots, through: :orders     has_many :radio_placements, through: :orders     has_many :newspaper_placements, through: :orders end  class order     has_many :television_spots     has_many :radio_placements     has_many :newspaper_placements end 

hopefully helps.