class ActiveRecord::ConnectionAdapters::MySQL::TableDefinition

def new_column_definition(name, type, **options) # :nodoc:
  case type
  when :virtual
    type = options[:type]
  when :primary_key
    type = :integer
    options[:limit] ||= 8
    options[:primary_key] = true
  when /\Aunsigned_(?<type>.+)\z/
    type = $~[:type].to_sym
    options[:unsigned] = true
  end
  super
end