Employee Short Leave Details and Hours Calculation in Oracle APPS

SELECT paa.person_id,

       paa.date_start,

       paa.date_end,

       time_start,

       time_end,

       ROUND (

          ( ( (SUBSTR (time_end, 1, 2) - SUBSTR (time_start, 1, 2)) * 60

             + (SUBSTR (time_end, 4, 2) - SUBSTR (time_start, 4, 2)))

           / 60),

          2)

          Hours

  FROM per_absence_attendances paa

      ,per_absence_attendance_types paat

 WHERE 1=1

   AND paa.absence_attendance_type_id = paat.absence_attendance_type_id

   AND paat.name = 'Short Leave'

   AND paa.date_start BETWEEN :p_period_start_date AND :p_period_end_date

   AND paa.date_end BETWEEN :p_period_start_date AND :p_period_end_date

   AND paa.person_id = 1234567890