Table A.E.60.1 - State University Enrollment

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

1) "a report on rooms occupied in a term"

2) "a report of each combination of student and course in a term"

3) "a report of each combination of course and school in a term regardless of student enrollment"

Select the corresponding cells in the APA and choose a cube to materialize, then highlight the derivatives of this cube.

Figure A.E.60.1 - The resulting APA with the redundancy free-set highlighted

Size of the redundancy-free set (including the base cube): 96

Required cubes, the materialization decision and derivatives

The blue area represents the end-user requirement 1 ("a report on rooms occupied in a term"), the end-user requirement 2 ("a report of each combination of student and course in a term") and the end-user requirement 3 ("a report of each combination of course and school in a term regardless of student enrollment").

Materializing cube v = (C_co, T_t, S_st, P_*) (dark blue cell "S_ro", representing end-user requirement 1), cube w = (C_co, T_t, S_st, P_*) (dark green cell "P_*", representing end-user requirement 2) and cube x = (C_co, T_t, S_*; P_sc) (red cell "P_sc", representing end-user requirement 3) offer us the following sets of derivatives.

Figure A.E.60.2 - Derivatives of cube v = (C_co, T_t, S_st, P_*)

Figure A.E.60.3 - Derivatives of cube w = (C_co, T_t, S_st, P_*)

Figure A.E.60.4 - Derivatives of cube x = (C_co, T_t, S_*; P_sc)

Figures A.E.60.2 to A.E.60.4 show that end-user requirement 1is covered by the derivatives of the vector w (end-user requirement 2). To meet all end-user requirements we will only have to materialize two cubes, wand x.