Summary

In this chapter, we demonstrated ODS as a new technique that allows us to build a multilayer structure for detail reporting at different levels. In particular, we completed the path in Figure 9.2 indicated by solid lines.

Along the way, we discovered some differences between ODS objects and 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.
• The default update type for an ODS object is Overwrite, and the default update type for an InfoCube is Addition.
• Data must be loaded into ODS objects via PSA. InfoCubes do not have this restriction. ODS objects use 0RECORDMODE values to implement the delta update.

Key Terms

Term	Description
ODS	ODS is a BW architectural component that appears between PSA and InfoCubes and that allows BEx reporting. It is not based on the star schema and is used primarily for detail reporting, rather than for dimensional analysis. ODS objects do not aggregate data as InfoCubes do. Data are loaded into an ODS object by inserting new records, updating existing records, or deleting old records as specified by 0RECORDMODE value.
Full update	The Full update option in the InfoPackage definition requests that BW load all data that meet the selection criteria specified under the Select data tab.
Delta update	The Delta update option in the InfoPackage definition requests that BW load only the data that have been accumulated since the last update. Before performing a delta update, the delta process must be initialized.

For Further Information

• OSS Note 0364577, "ODS: ORA-54 When Loading Data into the ODS."

• SS Note 0384023, "Optimize Performance of ODS Objects."

Next…

We will discuss Business Content and learn how to use it.