System::TDateTime __fastcall
      SubtractDayTimeFromDateTime(System::TDateTime Value, __int64
      DayTimeInterval, TEDBDayTimeIntervalType DayTimeIntervalType)

 In ElevateDB, day-time intervals are Int64 values that represent the number of milliseconds that have elapsed between two points in time. Use the TEDBEngine DayTimeIntervalToSQLStr method to convert a day-time interval into a readable string.