SAP BW - Day 3

On day 3 of SAP BW 360 - Performance and Administration, we learn about aggregrates.
What the heck is an aggregrates? Well, in short, it's just another mini
cute little infocube, which further aggregrates the bigger infocube.

Well it means that, let say you have A,B,C and D characteristics. So, in the minicube, it will combine, for example, A,B characteristics only. Which means that, if the infocube has like 5 Million records, the minicube might contain, say 10K records. When you're querying the cube for A,B characteristics, instead of reading the whole 5 million records, it will query the smaller mini infocube reading 10K records. Which results in better query performance.

Yeah,yeah, it's good and all, but, aggregrates takes extra storage space, and maintenance could be hell. Considering you have to run the 'attribute change run' to propagate any changes of master data to the aggregrates mini cube.

So how do you know which characteristics are a good candidate for aggregrates? The answer my friend lies in the power of SAP BW Statistical Information! After the BW is in production for quite sometime, BW will gather some useful statistics which you can use to tune performance. This also includes which characteristics combination is used the most. This characteristics combination, is a good candidate for aggregrates. So, you can let the system propose to you which aggregrates to create, but you have to ensure that the statistical information of each cube is activated.

Or for a truly 'SAP BW Master', you can use your awesome power of foresight to predict which characteristics is a good candidate for aggregration!