 			_keyToNumericDataMapping = new Dictionary();
 			
 			//if it's string data - create list of unique strings
-			var dataType:String = getMetadata(ColumnMetadata.DATA_TYPE);
+			var dataType:String = _metadata.attribute(ColumnMetadata.DATA_TYPE);
 			if (data[0] is String || (dataType && dataType != DataTypes.NUMBER))
 			{
 				if (!dataType)

				_maxNumber = NaN;
			}
			_metadata.attribute(ColumnMetadata.DATA_TYPE).setChildren(dataType);
			_dataType = dataType == DataTypes.NUMBER ? Number : String;
			
			// save a mapping from keys to data
			for (index = 0; index < keysA.length; index++)

					if (secondaryKeyFilter.value == null)
						return value + TYPE_SUFFIX
					break;
				case ColumnMetadata.DATA_TYPE:
					return _dataType == String ? DataTypes.STRING : DataTypes.NUMBER;
			}
			
			return value;
