ActiveRecord Bang methods

If you need an ActiveRecord method to raise an exception instead of a false value in case of failure, you can add \! to them. This is very important. As some exceptions/failures are hard to catch if you don’t use ! on them. I recommended doing this in your development cycle to write all your ActiveRecord code this way to save you time and trouble.

Class User < ActiveRecord::Base
  validates :last_name, presence: true
end

User.create!(first_name: "John")
#=> ActiveRecord::RecordInvalid: Validation failed: Last name can't be blank

The ActiveRecord methods which accept a bang (\!) are:

• .create!
• .take!
• .first!
• .last!
• .find_by!
• .find_or_create_by!
• #save!
• #update!
• all AR dynamic finders