Maniging relations in rails -

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i working on application , have create model product has many pictures , main picture. want model situation through relations , not using additional boolean field can tell if 1 picture main picture or not. think solution use has_one , has_many relations in product both link picture don't know how this.

you're going need way distinguish "main" picture other pictures. can done in number of ways:

a separate database table, say, main_pictures

class product     has_many :pictures     has_one :main_picture end

or other attribute on picture. can boolean or other field. in example, below, we'll use boolean attribute named primary on pictures table.

class product     has_many :pictures     has_one :main_picture, -> { where(primary: true) } end

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