# File lib/dm-core/migrations.rb, line 716
        def type_map
          precision = Property::DEFAULT_PRECISION
          scale     = Property::DEFAULT_SCALE_BIGDECIMAL

          @type_map ||= super.merge(
            BigDecimal => { :primitive => 'NUMERIC', :precision => precision, :scale => scale },
            Float      => { :primitive => 'DOUBLE PRECISION'                                  }
          ).freeze
        end