public static String convertToString(org.apache.hadoop.hive.metastore.api.Date val) {
    if (val == null) {
      return "";
    }

    DateWritableV2 writableValue = new DateWritableV2((int) val.getDaysSinceEpoch());
    return writableValue.toString();
  }
Creates a String from the properties in this format:
   'property_name1'='property_value1',
   'property_name2'='property_value2',
   ...

Properties are listed in alphabetical order.

@param properties The properties to list.
@param exclude Property names to exclude.
ql/src/java/org/apache/hadoop/hive/ql/ddl/ShowUtils.java