Non-Cumulative vs. Cumulative KeyFigures for Inventory Cube Implementation?
A non-cumulative is a non-aggregating key figure on the level of one or more objects, which is always displayed in relation to time. Generally speaking, in SAP BI data modeling, there are two options for non-cumulative management. First option is to use non-cumulative management with non-cumulative key figures. Second option is to use non-cumulative management with normal key figures (cumulative key figures). For SAP inventory management, 0IC_C03 is a standard business content cube based upon the option of non-cumulative management with non-Cumulative key figures. Due to specific business requirements (this cube is designed primarily for detailed inventory balance reconciliation, we have to enhance 0IC_C03 to add additional characteristics such as Doc Number, Movement type and so on. The original estimated size of the cube is about 100 million records since we are extracting all history records from ECC (inception to date). We spent a lot of time to debate on if we should use non-cumulative key figures based upon the standard business content of 0IC_C03 cube. We understand that, by using Non-Cumulative key figures, the fact table will be smaller (potentially). But, there are some disadvantages such as following:
(1) We cannot use the InfoCube together with another InfoCube with non-cumulative key figures in a MultiProvider.
(2) The query runtime can be affected by the calculation of the non-cumulative.
(3) The InfoCube cannot logically partition by time characteristics (e.g. fiscal year) which makes it difficult for future archiving.
(4) It is more difficult to maintain non-cumulative InfoCube since we have added more granularity (more characteristics) into the cube.
Thus, we have decided not to use the Cumulative key figures. Instead, we are using cumulative key figures such as Receipt Stock Quantity (0RECTOTSTCK) , Issue Stock Quantity(0ISSTOTSTCK)
, Receipt Valuated Stock Value (0RECVS_VAL) and Issue Valuated Stock Value (0ISSVS_VAL). All of those four key figures are available in the InfoCube and are calculated during the update process. Based upon the study of reporting requirements, those four key figures seems to be sufficient to meet all reporting requirements.
In addition, since we have decided not to use cumulative key figures, we have removed non-cumulative key figures from the 0IC_C03 InfoCube and logically partitioned the cube by fiscal year. Furthermore, those InfoCube are fiscally partitioned by fiscal year/period as well.
To a large extent, we are going away from the standard business content cube, and we have a pretty customized cube here. We'd like to use this opportunity to seek some guidance from SAP BI experts. Specifically, we want to understand what we are losing here by not using non-cumulative key figures as provided by original 0IC_C03 business content cube. Your honest suggestions and comment are greatly appreciated!