I have a table employee_attendance which keeps track the time_in,time_out (they are date format in database) for an employee every day.There is a third attribute called workhours(calculated attribute actually), which calculates the workhours between these two time_in, time_out, and round the difference to quarter, for example, if the employee works 18minutes(0.3hrs), that should be 0.5hrs(two quarters).
The presentation of the result should be like this:
time_in time_out work_hours
11/07/2003 08:00 11/07/2003 09:13 1.25
11/10/2003 10:55 11/10/2003 11:13 0.5
Please tell me how to write the formula for the caluated attribute - workhours?