Beginner’s Guide to Real Time Data Access via Web Services in SAP NW-BI

By Arun Bala Ganesan, Wipro Technologies

Introduction

Some organizations require making decision based on real time up to-date details regarding certain process or product information. For Example: Stock markets, Communications, Defense, Aeronautics, Supply chain management etc. Here each of and every transaction data matters the most in making a decision at a priority level, and it’s very crucial to transfer data to the reporting side at shorter & regular intervals. RDA: Extracts data from BW with a high frequency from source systems & migrates it to BI system. Real time data acquisition which supports tactical decision-making is a framework for deriving information from data as data becomes more complex. Frequency is data transfer is quite high. Follows regular type of data transfer, where extracted data runs through extraction & transformation process. Although not true real-time, data transferred is physical data  

Example:  RDA using SAP Service API  

RDA in Extraction Layer

The core of RDA is the SAP Source systems. Other source systems can be linked to the concept of RDA only if they act as a Web service and transfer data via SOAP messages to SAP BI.  

Figure I: RDA in Extraction Layer  

For SAP systems, the data sources that need to be connect by RDA need to be explicitly marked as 'Real time enabled'. For Generic Data sources, you can specify if a data source is able to handle accesses in real-time or not. The decision if a Generic Data source needs to be marked as real time enabled depends, how generic deltas are created.

·         Condition 1:  The delta defining fields should enable a high performance access to new/modified data. I.e. delta defining field must be selective & must be max. Affected by different values

·         Condition 2:  If there is a recent extraction, identification of the relevant data records from delta creation must contain only those recent data records.

Via the SOAP services, the SOAP messages are directly written to the PSA level of the data source. Hence, the messages don't find a way into BI through extraction process. So a BI system does not require executing the extraction, but only the PSA data, which is further processed in the delta procedure.

Process Steps

Go to RSA1, and follow the steps as below. This is a DSO which has been copied from the cube. The name for this source DSO: DSO_SLS. The target DSO has a name: DSO SOAP (Technical Name: C_DSO_SO) Now, In Info provider section we can view the DSO's structure. It has got the following fields. Primary Key fields - Customer ID (TCS CUSTID; Technical Name is TC_CUSTID) & Material ID (TCS MATID; Technical Name is TC_MATID). Data Fields is Quantity (TCS_QTY; Technical Name is TC_QTY) & its Unit of measure (0UNIT)           Go to DSO Settings & choose 'Select Type'. There are 3 options in the DSO level to choose its type. We choose to play safe with Standard DSO. 

It should be noted that this DSO will have unique fields. That means no data must be repeated. Go to Data sources & we choose 'XML'. This option helps us choose the type of Data source we intend to use. It could be 'FLAT FILE', 'SAP...' or 'XML' etc. Since we are using WSDL demo, we'll choose XML for now. In 'Data Sources', we need to create the Application Component Area. We create an AC Area & provide its long description also in this step. In this step, under the newly created Application Component Area, we create a 'Data Source'. In short all DS are just objects & are collected under this Application Comp. Area, which is a sort of 'folder' for these objects.

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