message: Issue DATE + TIME
  Force template materialisation.
diff: @@ -29,6 +29,10 @@ date_t AddOperator::Operation(date_t left, int32_t right);
  template <>
  date_t AddOperator::Operation(int32_t left, date_t right);
  template <>
  +timestamp_t AddOperator::Operation(date_t left, dtime_t right);
  +template <>
  +timestamp_t AddOperator::Operation(dtime_t left, date_t right);
  +template <>
  interval_t AddOperator::Operation(interval_t left, interval_t right);
  template <>
  date_t AddOperator::Operation(date_t left, interval_t right);
  