view db/migrate/072_add_enumerations_position.rb @ 420:2008fa7fda29 bug_145

Track the project tree explicitly through recursive functions rather than using lft, rgt ordering. Fixes #145
author Chris Cannam <chris.cannam@soundsoftware.ac.uk>
date Tue, 10 May 2011 11:57:41 +0100
parents 513646585e45
children 622f24f53b42
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class AddEnumerationsPosition < ActiveRecord::Migration
  def self.up
    add_column(:enumerations, :position, :integer, :default => 1) unless Enumeration.column_names.include?('position')
    Enumeration.find(:all).group_by(&:opt).each do |opt, enums|
      enums.each_with_index do |enum, i|
        # do not call model callbacks
        Enumeration.update_all "position = #{i+1}", {:id => enum.id}
      end
    end
  end

  def self.down
    remove_column :enumerations, :position
  end
end