calculate time diffrence in pl/sql with shifts : i have two table 
the first table contains the record of a ticket with start date and end date.
 start_date           | End_Date
 21-02-2017 07:52:32  | 22-02-2017 09:56:32
 21-02-2017 09:52:32  | 23-02-2017 17:52:32

the second table contains the details of the weekly shift:
 shift_day | Start_Time | End_Time
  MON        9:00          18:00
  TUE        10:00         19:00
  WED        9:00          18:00
  THU        10:00         19:00
  FRI        9:00          18:00

I am looking to get the time difference in the first table which will only include the time as per the second table. 

