class Sequel::Migration

  1. lib/sequel/extensions/migration.rb
Parent: Sequel

Sequel’s older migration class, available for backward compatibility. Uses subclasses with up and down instance methods for each migration:

Class.new(Sequel::Migration) do
  def up
    create_table(:artists) do
      primary_key :id
      String :name
    end
  end

  def down
    drop_table(:artists)
  end
end

Part of the migration extension.

Public Class methods

apply (db, direction)

Applies the migration to the supplied database in the specified direction.

[show source] 
# File lib/sequel/extensions/migration.rb, line 35
def self.apply(db, direction)
  raise(ArgumentError, "Invalid migration direction specified (#{direction.inspect})") unless [:up, :down].include?(direction)
  new(db).send(direction)
end
descendants ()

Returns the list of Migration descendants.

[show source] 
# File lib/sequel/extensions/migration.rb, line 41
def self.descendants
  @descendants ||= []
end
inherited (base)

Adds the new migration class to the list of Migration descendants.

[show source] 
# File lib/sequel/extensions/migration.rb, line 46
def self.inherited(base)
  descendants << base
end
new (db)

Set the database associated with this migration.

[show source] 
# File lib/sequel/extensions/migration.rb, line 29
def initialize(db)
  @db = db
end
use_transactions ()

Don’t allow transaction overriding in old migrations.

[show source] 
# File lib/sequel/extensions/migration.rb, line 51
def self.use_transactions
  nil
end

Public Instance methods

down ()

The default down action does nothing

[show source] 
# File lib/sequel/extensions/migration.rb, line 56
def down
end
method_missing (method_sym, *args, &block)

Intercepts method calls intended for the database and sends them along.

[show source] 
# File lib/sequel/extensions/migration.rb, line 60
def method_missing(method_sym, *args, &block)
  @db.send(method_sym, *args, &block)
end
respond_to_missing? (meth, include_private)

This object responds to all methods the database responds to.

[show source] 
# File lib/sequel/extensions/migration.rb, line 65
def respond_to_missing?(meth, include_private)
  @db.respond_to?(meth, include_private)
end
up ()

The default up action does nothing

[show source] 
# File lib/sequel/extensions/migration.rb, line 70
def up
end