# File lib/dm-core/migrations.rb, line 301
        def type_map
          length    = Property::DEFAULT_LENGTH
          precision = Property::DEFAULT_PRECISION
          scale     = Property::DEFAULT_SCALE_BIGDECIMAL

          @type_map ||= {
            Integer       => { :primitive => 'INTEGER'                                           },
            String        => { :primitive => 'VARCHAR', :length => length                        },
            Class         => { :primitive => 'VARCHAR', :length => length                        },
            BigDecimal    => { :primitive => 'DECIMAL', :precision => precision, :scale => scale },
            Float         => { :primitive => 'FLOAT',   :precision => precision                  },
            DateTime      => { :primitive => 'TIMESTAMP'                                         },
            Date          => { :primitive => 'DATE'                                              },
            Time          => { :primitive => 'TIMESTAMP'                                         },
            TrueClass     => { :primitive => 'BOOLEAN'                                           },
            Types::Object => { :primitive => 'TEXT'                                              },
            Types::Text   => { :primitive => 'TEXT'                                              },
          }.freeze
        end