rails validate uniqueness
To validate the uniqueness of a field in Ruby on Rails, you can use the validates
method in the model file. First, specify the field you want to validate as unique using the uniqueness
option. Then, you can add an error message if the validation fails using the message
option. Here's an example:
class User < ApplicationRecord
validates :username, uniqueness: { message: "This username is already taken" }
end
In this example, the User
model validates the uniqueness of the username
field and provides a custom error message if the validation fails.