code: public void setAttributePropertiesInDB(final String attributeName, final Map<String, String[]> properties)
              throws DevFailed {
          xlogger.entry(properties);
  
          final Map<String, String> currentValues = getAttributePropertiesFromDBSingle(attributeName);
          final Map<String, String[]> propInsert = new HashMap<String, String[]>();
          for (final Entry<String, String[]> entry : properties.entrySet()) {
              final String propertyName = entry.getKey();
              final String[] valueArray = entry.getValue();
              // insert value in db only if input value is different and not a
              // default value
              if (valueArray.length == 1) {
                  final String value = valueArray[0];
                  final String presentValue = currentValues.get(propertyName);
                  boolean isADefaultValue = false;
                  if (presentValue != null) {
                      isADefaultValue = presentValue.isEmpty()
                              && (value.equalsIgnoreCase(Constants.NOT_SPECIFIED)
                                      || value.equalsIgnoreCase(Constants.NO_DIPLAY_UNIT)
                                      || value.equalsIgnoreCase(Constants.NO_UNIT) || value
                                          .equalsIgnoreCase(Constants.NO_STD_UNIT));
                  }
                  if (!isADefaultValue) {
                      if (presentValue == null) {
                          propInsert.put(propertyName, valueArray);
                      } else if (!presentValue.equals(value) && !value.isEmpty() && !value.equals("NaN")) {
                          propInsert.put(propertyName, valueArray);
                      }
                  }
              } else {
                  // do not check if not a single value
                  propInsert.put(propertyName, valueArray);
              }
          }
          logger.debug("update attribute {} properties {} in DB ", attributeName, properties.keySet());
          DatabaseFactory.getDatabase().setAttributeProperties(deviceName, attributeName, propInsert);
          xlogger.exit();
      }
docs: Set attribute properties in tango db
  
  @param attributeName
  @param properties
  @throws DevFailed