a = Appointment 1 start A = Appointment 1 end b = Appointment 2 start B = Appointment 2 end The only predicates are: a < A, b < B The complete set of or

a = Appointment 1 start A = Appointment 1 end b = Appointment 2 start B = Appointment 2 end The only predicates are: a < A, b < B The complete set of orderings are thus: aAbB - no overlap bBaA - no overlap abAB - partial overlap baBA - partial overlap abBA - complete overlap of one appointment inside the other baAB - complete overlap of one appointment inside the other