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Exercise No. 38: Advertising Campaign (apa)

As the result of DFM Case "advertising campaign" this cube stores data about an advertising campaign.

We have five dimensions with the following hierarchical structure:

Table A.E.24.1 - advertising campaign

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 continent independent of all other dimensions"

2) "a monthly report on product groups independent of all other dimensions"

3) "a complete drill-down by the time dimension down to month for each combination of advertising agency and product group, irrespective of the other dimensions"

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

Solution

Figure A.E.24.1 - The resulting APA with the redundancy free-set highlighted

Size of the redundancy-free set (including the base cube): 144

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 continent independent of all other dimensions"), requirement 2 ("a monthly report on product groups independent of all other dimensions") and requirement 3 ("a complete drill-down by the time dimension down to month for each combination of advertising agency and product group, irrespective of the other dimensions").

Materializing cube v = (CO_*,A_*,C_con,P_*,T_y) (dark blue cell "T_y", representing end-user requirement 1), cube w = (CO_*,A_*,C_*,P_gr,T_m) (dark green cell "P_gr", representing end-user requirement 2) and cube x = (CO_*,A_aa, C_*,P_gr,T_m) (red cell "P_gr", representing end-user requirement 3) offer us the following sets of derivatives.

Kein Bild hinterlegt

Figure A.E.24.2 - Derivatives of cube v = (CO_*,A_*,C_con,P_*,T_y)

Figure A.E.24.3 - Derivatives of cube w = (CO_*,A_*,C_*,P_gr,T_m)

Figure A.E.24.4 - Derivatives of cube x = (CO_*,A_aa, C_*,P_gr,T_m)

Figures A.E.24.2, A.E.24.3 and A.E.24.4 show that end-user requirement 2 is covered by the derivatives of x. Considering that w can easily be derived from x = (CO_*,A_aa, C_*,P_gr,T_m) by aggregation along only one dimension simplifies the materialization decision:

To meet all end-user requirements we will only have to materialize the cube v and x.

This exercise is part of a case study: dfm - apa - log

Exercises List