> >

> >

> > Hi Cetin

> > Did you mean calculate it at the time of clock-in/out? I'm interested to know why, if you could give an example. Thanks.

> >

> > Regards

> > Samir

>

> A calculated column is something that is calculated from other persistent columns (and the calculated column itself could be persistent and indexed). I meant something like this:

>

> InTime: datetime(2011,6,27, 10,15, 30)

> OutTime: datetime(2011,6,27, 20,0,0)

> FromSeconds: 36930 (this is calculated - column is a formula)

> ToSeconds: 72000

>

> If you keep aside the situation of having in and out on different dates (and you could also cover it if you store ticks instead) then those integer values serve as start-end points of a line (visualize). Including different dates it more looks like top-left and bottom-right of a rectangle and thus helps finding out overlapping times. Consider a tutor is on vacation between X1,Y1 and X2,Y2 (rectangle formed from datetimes) and a student wants to book an appointment with him on X3,Y3 (like a point in time - with duration a line). Is that time overlapping tutor's off time? You can make the calculation using datetimes directly but I found it easier using such integers (especially when the back end is VFP where you cannot compare datetime values directly).

>

> Cetin Basoz

>

>

**.Net has got better.**Think about moving - check my blog:

>

My Blog>

Blog (mirror) - sounds to be downThank you for the example and explanations Cetin, I understood in theory. I don't know how it would be if I had to put that in practice. I'll mark this thread and keep it in case I need this some day.

Regards

Samir