lets assume we have people table with schema like this

# Table name: people
#
#  id               :integer          not null, primary key
#  name             :string(255)
#  created_at       :datetime
#  updated_at       :datetime
#  terms_of_service :boolean

and Person model defined like this

class Person < ActiveRecord::Base
  validates :name, presence: true
  validates :terms_of_service, acceptance: true
end

when you trying to save your data

>> Person.create(name: "pyk", terms_of_service: false).errors
   (0.4ms)  BEGIN
   (0.6ms)  ROLLBACK
=> #<ActiveModel::Errors:0xba205264 @base=#<Person id: nil, name: "asssS", created_at: nil, updated_at: nil, terms_of_service: false>, @messages={:terms_of_service=>["must be accepted"]}>
>> Person.create(name: "pyk", terms_of_service: true).errors
   (0.4ms)  BEGIN
   (0.4ms)  ROLLBACK
=> #<ActiveModel::Errors:0xba1ea4f0 @base=#<Person id: nil, name: "asssS", created_at: nil, updated_at: nil, terms_of_service: true>, @messages={:terms_of_service=>["must be accepted"]}>

whenever you insert true or false in terms_of_service column, it’s always return an error.

@messages={:terms_of_service=>["must be accepted"]}

first, you need to now is acceptance used without such a column, in which case it defines an attribute accessor and uses that for its validation. so when we provide terms_of_service column it make our validation always failing.

remove terms_of_service column

you have to remove this column to get validation helper work. but, if you think it’s important to use terms_of_service column you can use the next solution.

add :accept option

class Person < ActiveRecord::Base
  validates :name, presence: true
  validates :terms_of_service, acceptance: {accept: true}
end

now your validation should work flawlessly.

>> Person.create(name: "pyk", terms_of_service: true).valid?
   (0.3ms)  BEGIN
  SQL (8.0ms)  INSERT INTO "people" ("created_at", "name", "terms_of_service", "updated_at") VALUES ($1, $2, $3, $4) RETURNING "id"  [["created_at", Tue, 11 Feb 2014 14:29:40 UTC +00:00], ["name", "pyk"], ["terms_of_service", true], ["updated_at", Tue, 11 Feb 2014 14:29:40 UTC +00:00]]
   (67.9ms)  COMMIT
=> true
>> Person.create(name: "pyk", terms_of_service: false).valid?
   (0.4ms)  BEGIN
[deprecated] I18n.enforce_available_locales will default to true in the future. If you really want to skip validation of your locale you can set I18n.enforce_available_locales = false to avoid this message.
   (0.7ms)  ROLLBACK
=> false