Data Store Objects
Since a DataStore object is designed like a table, it contains key fields (document number and item, for example) and data fields. Data fields can not only be key figures but also character fields (order status, customer, or time, for example). You can use a delta update to update DataStore object data into connected InfoCubes or into additional DataStore objects or master data tables (attributes or texts) in the same system or in different systems. In contrast to multidimensional DataStores for InfoCubes, data in DataStore objects is stored in flat, transparent database tables. Fact and dimension tables are not created.
With DataStore objects, you can not only update key figures cumulatively, as with InfoCubes, but also overwrite data fields. This is especially important for transaction-level documents that change in the source system. Here, document changes not only involve numerical fields, such as order quantities, but also non-numerical ones such as ship-to parties, delivery date, and status. Since the OLTP system overwrites these records when changes occur, DataStore objects must often be moceled to overwrite the corresponding fields and update to the current value in BI.
DS Oject Types
SAP BI distinguishes between three DataStore object types: Standard, Write Optimized, and Direct Update. These three flavors of DataStore Objects are shown in the following figure.
1. The Standard DataStore Object consists of three tables (activation queue, active data table, and change log). It is completely integrated in the staging process. In other words, data can be loaded into and out of the DataStore Objects during the staging process. Using a change log means that all changes are also written and are available as delta uploads for connected data targets.
Architecture and Functions of Standard DataStore Objects
Architecture and Functions of Standard DataStore Objects
Standard DataStore objects consist of three tables:
Active Data table
This is where the current status of the data is stored. This table contains a semantic (business-related) key that can be defined by the modeler (order number, item, or schedule line, for example). It is very important that the key be correctly defined by the modeler, as a match on the key initiates special delta processing during the activation phase (discussed later). Also, reporting via the BEx uses this table.
Change Log table
During the activation run, changes are stored in the change log. Here, you can find the complete history of the changes, since the content of the change log is not automatically deleted. The connected targets are updated from the change log if they are supplied with data from the DataStore object in the delta method. The change log is a PSA table and can also be maintained in the PSA tree of the Data Warehousing Workbench. The change log has a technical key consisting of a request, data package, and data record number.
Activation Queue table
During the DTP, the records are first written to this table. This step is necessary due to the complex logic that is then required by the activation process.
Schema for a Standard DataStore Objects
2. Write optimized is a new kind of DataStore Object . It is targeted for the warehouse level of the architecture, and has the advantage of quicker loads.
3. A direct update DataStore object (previous 3.x transactional ODS) has only the table with active data. This means it is not as easily integrated in the staging process. Instead, this DataStore object type is filled using APIs and can be read via a BAPI.
