public static void appendNonNull(StringBuilder builder, Object value, boolean firstColumn) {
    if (!firstColumn) {
      builder.append((char)Utilities.tabCode);
    } else if (builder.length() > 0) {
      builder.append((char)Utilities.newLineCode);
    }
    if (value != null) {
      builder.append(value);
    }
  }
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