>Hi,
> I am developing an time attandance system.
> I faced a problem on calculating the working hours of workers who are work in shift and cross date (e.g. 23:00:00 -> 05:00:00).
> How will you design the algorithm to calculate the working working in this case?
>
>Thank you

If you just want the time worked then store datetime and you shouldn't have a problem.

As for what day to report on, I have always used the date of the starting datetime to define the starting day.