Operational Data Store (ODS)
In Section 7.5, we discussed line item dimensions as a technique for detail reporting. In this chapter, we will demonstrate another technique, Operational Data Store (ODS). It allows us to build a multilayer structure for detail reporting at different levels, including the line item level.
Specifically, ODS is a BW architectural component located between PSA and InfoCube (Figure 9.1). The ODS layer itself can contain multiple ODS objects with data at different levels of detail.
Figure 9.1. ODS IN BW
As shown in Figure 9.1, there are many ways to send data to their destinations. If one destination is an ODS object, then as BW 2 releases the data, it must be loaded into PSA first, then from PSA to the ODS object. We will explain the reason for this in Section 9.3, "Loading Data into the ODS Object."
Like InfoCubes, ODS objects allow BEx reporting. Unlike InfoCubes, ODS objects are not based on the star schema and should not be used for multidimensional analysis. For the same reason, ODS objects do not aggregate data as InfoCubes do, cannot have aggregates, and cannot be included in a multi-cube. Other differences are described later in this chapter.
In this chapter, we will create an ODS object, load data into it, and then load the data from the ODS object into an InfoCube. The solid lines in Figure 9.2 represent this procedure.
Figure 9.2. DATA FLOW