ruby on rails - has_many belongs_to association with a foreign key -

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let's have 2 models venue , photo. each venue can have many photos, can have one featuredphoto. each photo can belong many venues , can featuredphoto of more 1 venue too.

i have general has_and_belongs_to_many relationship set , working through join table these models:

class photo < activerecord::base   mount_uploader :image, photouploader   has_and_belongs_to_many :venues end  class venue < activerecord::base   has_and_belongs_to_many :photos end

to add featuredphoto, seems need add column called featured_photo_id venue model , set has_many, belongs_to association between two. i'm not sure add foreign_key info. right?

class photo < activerecord::base   mount_uploader :image, photouploader   has_and_belongs_to_many :venues   has_many :venues end  class venue < activerecord::base   has_and_belongs_to_many :photos   belongs_to :photo, foreign_key: "featured_photo_id", class_name: "photo" end

or have add foreign_key info both models?

this can achieved if add model intermediate table photosvenue , add boolean column is_featured in intermediate table.

i created demo app want. check github repo

hope helps :)


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