Dates: calculating elapsed time
Am building a satabase that's essentially a timeline, viz:
date 1 - date 2: place 1
date 2 - date 3: place 2
date 3 - date 4: place 3
But occasionally a long span, say:
date 4 - date 5: place 4
is interrupted by a shorter span:
date 5 - date 6: place 5
only to be resumed afterwards:
date 6 - date 7: place 4 again.
Would someone kindly point me towards the best soures to look for this kind of functionality, please?
In short, are their functions (in FMP11, 12) that allow me to calculate and store date spans even when they're discontinuous?