Non-cumulatives (SAP Library - Non-cumulatives)

Non-Cumulatives

Definition

Non-cumulatives need their own store as they are measured relative to a point in time and need a special aggregation.

Therefore, a distinction is made between two types of key figures: Cumulative values and non-cumulative values. A cumulative value is a key figure that is measured in relation to a time period. Such key figures (for example, sales revenue by division) can be aggregated with regard to time, that is, added up over several periods. Non-cumulative values are key figures that cannot be usefully added over time. With non-cumulative values such as "Number of Employees", it is not useful to add up the number of employees over different periods, but rather to form the average over the period. In the case of stock prices, for example, it is the maximum, minimum and mean values within a time period that are important, and not the total.

Both types of key figure differ in their aggregation behavior. Non-cumulative values are summarized over time using exception aggregation. If you add up all the cumulative values such as "sales revenue" using all characteristics (that is, time characteristics as well), the non-cumulative value relating to the time characteristic is often taken as the average or the last value.

Example

Non-cumulative values such as ‘number of employees’, are cumulated using characteristics such as ‘cost center’. Non-cumulative values such as ‘number of employees’, are cumulated using characteristics such as ‘cost center’. With periods, for example, you can form an average.

With the cumulative value ‘sales revenue’, for example, it makes sense to cumulate the individual sales revenues using different periods, and using characteristics such as ‘products’ and ‘customers’.

Example of the difference between non-cumulative and cumulative values:

Sales revenue (cumulative value):

Sales volume 01.20 + sales volume 01.21 + sales volume 01.23 gives the total sales volume for these three days.

Warehouse stock (non-cumulative value):

Stock 01.20 + stock 01.21 + stock 01.23 does not give the total stock for these three days.

There are two possible kinds of aggregational behavior for non-cumulative values:

The standard aggregation specifies how a key figure is compressed using all characteristics (but not time characteristics).
The exception aggregation specifies how a key figure is compressed using all time characteristics.

Use

The target of the special folder for non-cumulative values is to optimize the data transport into BW, to retain data, and to access the database when evaluating for reports in BW. The data transfer from the source system is minimized and only the meaningful data is saved and processed.

It is recommended that you use non-cumulative values for areas in which non-cumulatives do not regularly change completely, for example with warehouse stock (retail) or with the number of employees.

Structure

Model of Non-Cumulative Values

Non-cumulatives are modeled in BW using a non-cumulative value and its fields for changing the non-cumulative or for receipts or issues.

Technically, non-cumulatives are stored using a marker for the current time (current non-cumulative) and the storage of non-cumulative changes, or inflows and outflows. The current, valid end non-cumulative (to 12.31.9999) is stored in the marker. You can determine the current non-cumulative or the non-cumulative at a particular point in time. You can do this from the current, end non-cumulative and the non-cumulative changes and/or the inflows and outflows.

Queries for the current non-cumulative can be answered very quickly, since the current non-cumulative is created as a directly accessible value. There is only one marker for each combination of characteristic values that is always updated when the non-cumulative InfoCube is compressed. So that access to queries is as quick as possible, compress the non-cumulative InfoCubes regularly. (See Compressing InfoCubes) to keep the marker as up to date as possible.

Example

For example, in month 03 the marker is read with three non-cumulative changes for a query. In month 04, the marker is updated so that the current marker has to be read with only one non-cumulative change for a query in month five. If the marker is not updated, it still has four non-cumulative changes to read

The non-cumulative changes or the inflows and outflows are cumulative values in themselves and can be used separately as key figures or in query structures.

Data Transfer or Storage, and Aggregation for Non-Cumulative Values

To optimize the data transport and data retention for non-cumulative values in BW, non-cumulative values are treated differently to cumulative values in both technical data transfer and storage, as well as in aggregation:

Features of Non-Cumulative Values: Transferring and Saving Data:

Non-cumulative values are mapped using one key figure for non-cumulative changes or two key figures for inflows and outflows.