Validation of Rails requires numerical strength, even if presence is not set to true

Question

I am trying to save a record that does not have one set of fields that has a numeric check value in models. Although the presence is not required in the check, it still throws an error that the field is not a number.

Validation:

validates :network_id, :numericality => true 

Code to save the model:

 networks.each do |network| network.url = network.raw_data.link network.save! end 

Mistake:

 Validation failed: Network is not a number 

Answer 1

 validates :network_id, :numericality => true, :allow_nil => true 

Answer 2

  validates :network_id, :numericality => {:allow_blank => true} 

Answer 3

You must use allow_blank

 validates :network_id, :numericality => true, :allow_blank => true 

Answer 4

In Rails 4 (Ruby 2) you can write:

 validates :network_id, numericality: { greater_than_or_equal_to: 0, allow_nil: true }