You only need to initialize the delta process once, after SAP BW has been connected to SAP CRM. During initialization, all data that can be extracted using a DataSource is transferred from SAP CRM into SAP BW.
You need to have executed all actions that are necessary for data extraction into SAP BW. For more information, choose Business Information Warehouse ® Administrator Workbench ® Source System in the SAP BW documentation in the SAP Library.
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1. You execute the initialization of the delta process in SAP BW by creating and scheduling a corresponding InfoPackage. For more information, choose Business Information Warehouse ® Administrator Workbench ® Scheduler in the SAP BW documentation in the SAP Library.
2. SAP BW calls up the BW Adapter using the Service API.
The following steps depend on the BW Adapter metadata for the DataSource used. You do display the BW Adapter metadata in Customizing for CRM under Integration with Other mySAP Components ® Data Transfer into SAP Business Information Warehouse ® Settings for Application-Specific DataSources (CRM) ® Settings for BW Adapter ® Activate BW Adapter Metadata ® Maintain DataSource and Enhance BW Adapter Metadata. In this activity, you can also enhance DataSources for sBDoc types. For information on the procedure, see the documentation about this IMG activity.
3. The BW Adapter reads the data from the respective database:
In the case of the BDoc type "mBDoc", from the application database
In the case of the BDoc type "sBDoc", from the consolidated database (CDB)
4. The selected BDoc data is converted into the extract structure from a mapping module that is also entered in the BW Adapter metadata.
5. The type of Business Add-In (BAdI) that is called up by the BW Adapter depends on the BDoc type:
sBDoc type: CRM_BWA_SFLOW
In this BAdI, you can change the assignments delivered by SAP. If you have
enhanced the DataSource (see step 2), also program the assignments for the
enhanced fields in this BAdI. For a full explanation, refer to the BAdI
documentation.
mBDoc type: CRM_BWA_MFLOW
In this BAdI, you can change the assignments delivered by SAP.
6. The requested data package is transferred to SAP BW using the Service API.
All the data for the DataSource is extracted into SAP BW. You can now copy the respectively changed data using the delta upload.