Table A.E.14.1 - Service Management

Please build the Aggregation Path Array and assume the following end-user requirements:

1) "a roll-up by the time dimension starting at years, for each technician and problem type, independent of customers"

2) "a monthly report on problem types, irrespective of customers and technicians"

Select the corresponding cells in the APA and choose the cubes to materialize, then highlight the derivatives of those cubes.

Figure A.E.14.1 - The resulting APA with the redundancy free-set highlighted

Size of the redundancy-free set (including the base cube): 108

Required cubes, the materialization decision and derivatives

The blue area represents the end-user requirement 1 ("a roll-up by the time dimension starting at years, for each technician and problem type, independent of customers") and requirement 2 ("a monthly report on problem types, irrespective of customers and technicians").

Materializing cube v = (P_ty, C_*,E_te,T_y) (dark blue cell "T_y", representing end-user requirement 1) and cube w = (P_ty,C_*, E_*, T_m) (dark green cell "E_*", representing end-user requirement 2) offer us the following sets of derivatives.

Figure A.E.14.2 - Derivatives of cube v = (P_ty, C_*,E_te,T_y)

Figure A.E.14.3 - Derivatives of cube w = (P_ty,C_*, E_*, T_m)

Figures A.E.14.2 and A.E.14.3 show that end-user requirement 2 is not covered by the derivatives of v. To meet all end-user requirements we will have to materialize both cubes, v and w.