• The transaction data entering the Business Information Warehouse by means of extractors originates from very different modules. Due to past developments, very different extraction mechanisms are necessary.
• Before you start an SAP BW project (and also if BW is already in productive use), you will probably think about the reports you want to run and the data you need from the R/3 System.• You will then have to take a look at the sources shipped with SAP Business Content to decide which ones meet your requirements and can be used by default.• If you need data that cannot be supplied by the standard sources, you can: Create new InfoSources Enhance the standard ones
• Each time a DataSource is generated, the corresponding transfer and communication structures are also generated in the BW System. Transfer structures always exist in pairs - in a source system and in the associated SAP BW System. This transfer structure is used to transfer data in the format of the original application from a source system to BW, where it is forwarded to the communication structure of the InfoSource using transformation rules.• The communication structure is independent of the source system and contains all of the fields in the InfoSource that it represents in BW.
• Replicating DataSources• The DataSource is replicated in BW.• Fields in the OLTP extract structure that have been assigned InfoObjects are made available in a template DataSource in BW.• Assigning InfoSources The DataSource is assigned to an InfoSource.• Maintaining the Communication Structure The communication structure is generated from the selected fields in the template InfoSource in BW.• Creating Transfer Rules The transfer structure is generated from the selected InfoObjects in the template DataSource in BW and in the R/3 OLTP System.
• SAP provides extractors for almost all applications.• These extractors are programmed on a fixed basis and shipped with Business Content. However, some Business Content extractors do use the technology of the cross-application generic extractors.• Business Content is developed and enhanced with every new BW Release.
• In response to demands from our customers, SAP has designed the reporting facility in certain parts of the R/3 System in such a way that it can be easily customized. Information systems were developed in the R/3 System that can be adapted individually to the customers requirements.• The Business Information Warehouse must be able to process this data, with the result that it must be possible to define generic extractors in certain applications. These applications are the Logistics Information System, profitability analysis and Special Ledger.
• Each individual application provides tools for this purpose. But first, you have to generate a DataSource from a selected data base in the application.• Following this, you have to assign attributes to the fields of the extract structure / DataSource (for example, selectability).• Depending on the application, certain settings may have to be made. In this example, activating the delta update in the LIS.
• Data supplied to customer tables in an R/3 System by programs developed in-house can also be transferred to BW. This includes data in R/3 tables that are supplied by SAP programs but cannot be made available to the Business Information Warehouse with Business Content.• The tool for generic data extraction can be used here to generate an extractor for all applications. By assigning a database view or transparent database table, you can transfer data to BW without having to write your own programs.
• Several steps are also required to create extractors using the generic data extraction tool (transaction RS02). These are basically as follows:• Create a DataSource with the generic data extraction tool (transaction RSO2)• If necessary, create a view or an InfoSet (functional area).• The fields in the DataSource must then be assigned InfoObjects. If these InfoObjects are not available, they must be created.
Update Methods• Data can be imported into BW using two different update methods: a full update, in which all of the data is extracted, and a delta update, in which only the data that has been changed or added since the last import run is extracted.• Naturally, a delta update is particularly suitable for large quantities of data so that the same data does not have to be imported into BW several times.
• A delta management tool (change log) is provided for the most important master data, which can have a very large number of characteristic instances in the R/3 OLTP System. These characteristics are the material, batch number, plant, creditor, debtor, cost center, cost component, activity type and G/L account.
• As far as the transaction data is concerned, Business Content is shipped with extractors in SD and HR, which support delta processes. Within the LO module, a central delta management is used. In LIS and CO/PA, all application-specific generated extractors support a delta process. Delta updates in the LIS are based on separate delta tables. The CO/PA module, on the other hand, uses a timestamp.
• A delta process is not implemented for the cross-application generic data extraction tool. Delta extraction in this case can only be carried out by suitable selections using a creation and change date.