activerecord - Rails 4: How Can I filter records that have no has_many records matching a certain criteria? -


here problem having: have app questions object, has_many answers. answers have status attribute, can equal accepted.

how can write activerecord query return questions have 0 accepted answers? have tried currently:

 class question < activerecord::base    has_many :answers     def self.needs_answers      self.includes(:answers).group('questions.id').where('answers.id not null or answers.status != 'accepted').references(:answers)    end  end

however, if question has 2 answers, 1 accepted , 1 not, still returned query. how can filter these records out?

there may other ways complex count-based join/having, simplest way can think solve using sub-select:

def self.needs_answers   where.not id: joins(:answers).where(answers:{status: 'accepted'}) end

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