Table A.E.7.1 - Writing articles

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

1) "a monthly report for each subject group irrespective of the author, the lector and the newspaper"

2) "a roll up by the time dimension starting at years for each author and article subject group independent of the newspaper and lector"

3) "an annual report for each lector, including the newspaper type, irrespective of the author and the article"

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

Figure A.E.7.1 - 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 monthly report for each subject group irrespective of the author, the lector and the newspaper"), requirement 2 ("a roll up by the time dimension starting at years for each author and article subject group independent of the newspaper and lector") and requirement 3 ("an annual report for each lector, including the newspaper type, irrespective of the author and the article").

Materializing cube v = (AU_*,LE_*,AR_sg,NE_*,T_m) (dark blue cell "NE_*", representing end-user requirement 1), cube w = (AU_au,LE_*,AR_sg,NE_*,T_y) (dark green cell "T_y", representing end-user requirement 2) and cube x = (AU_*,LE_le, AR_*,NE_ty,T_y) (red cell "T_y", representing end-user requirement 3) offer us the following sets of derivatives.

Figure A.E.7.2 - Derivatives of cube v = (AU_*,LE_*,AR_sg,NE_*,T_m)

Figure A.E.5.3 - Derivatives of cube w = (AU_au,LE_*,AR_sg,NE_*,T_y)

Figure A.E.7.4 - Derivatives of cube x = (AU_*,LE_le, AR_*,NE_ty,T_y)

Figures A.E.7.2, A.E.7.3 and A.E.7.4 show that no end-user requirement is covered by the derivatives of another cube. To meet all end-user requirements we will have to materialize all three cubes, v, w and x.