ActiveRecord::Mysql::Enum

This gem is an extension to ActiveRecord which enables native support of enumerations in the database schema using the ENUM type in MySQL. Forked and revitalized from enum_column3 which was itself a fork of a fork of Nick Pohodnya's original gem for Rails 3, enum_column3.

Currently this is tested with ActiveRecord version 5.2, 6.0, 6.1, and 7.0.

Supported adapters:

• mysql2

In your Gemfile add the following snippet

gem 'activerecord-mysql-enum', '~> 2.0', require: 'active_record/mysql/enum'

In order to initialize the extension in non-Rails applications, you must add the following line to your application's bootstrapping code after ActiveRecord has been initialized.

ActiveRecord::Mysql::Enum.initialize!

When defining an enum in your schema, specify the constraint as a limit:

create_table :enumerations, :force => true do |t|
  t.column :severity, :enum, :limit => [:low, :medium, :high, :critical], :default => :medium
  t.column :color, :enum, :limit => [:red, :blue, :green, :yellow]
end

You can then automatically validate this column using:

validates_columns :severity, :color

All enumerated values will be given as symbols.

@e = Enumeration.new
@e.severity = :medium

You can always use the column reflection to get the list of possible values from the database column.

irb(1)> Enumeration.columns_hash['color'].limit
=> [:red, :blue, :green, :yellow]
irb(2)> @enumeration.column_for_attribute(:color).limit
=> [:red, :blue, :green, :yellow]