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Rails Validation - Maximum Database Records

I have a rails project using an active record and I was wondering if there is a validation helper for the maximum number of individual records. For example, if you had a form view and only want to say 2 and you just need the first 2 to be stored in the table, how would you do that?

I read the manual and took a look at the numbers and so on, but that's not exactly what I'm looking for. I tried to write my own validation method in the model, but I'm guessing there is a validation helper that makes this easier:

  def validatePassengerNumber 
    if self.passengers.length > 2
      # unsure on how to refuse new data access to database
    end
  end
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3 answers


Add an error to the database after checking to return true and it will prevent saving to the database.

 def validate_passenger_number        
     self.errors.add(:base, "exceed maximum entry") if self.passengers.length > 2
 end


Call this custom check on the appropriate model.

  validate :validate_passenger_number, on: :create
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No built-in validation; at least I haven't met anyone. But here's a way to enforce this type of validation:

  def max_passengers
    if self.passengers.count > 2
      errors.add_to_base("There should not be more than 2 passengers.")
    end
  end


And then you can use that check to put a check on the number of passengers.

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You can add a callback and confirm the entry.

before_validation :validate_passanger_number

private

def validate_passanger_number
  errors.add("Sorry", "you have added maximum passengers.") if self.passengers.count > 2
end
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