Note: The below scenario is applicable only for the datasources 0FI_GL_4 (General ledger: Line Items),0FI_AP_4(Accounts payable: Line Items), 0FI_AR_4 (Accounts receivable: Line Items)
Scenario
In BW, the delta extraction for 0FI_GL_4 from the source system can be loaded as per the processchain or infopackage schedule but where as, from source system will be able to fetch the delta records as per the timestamp defined, or depending on system predefined delta pointer. So even if the data is pulled multiple times Ex:- for every 30 minutes in the same day in the BW system, the deltas will fetch zero records, if the delta pointer is limited to certain period for Ex:- only once a day in the source system.
Check the below link:
Financial Accounting: Procedure for Line Item Extraction
Constraints
Per day, no more than one delta dataset can be transferred for InforSource 0FI_GL_4. The extracted data therefore has the status of the previous day. For further data requests on the same day, the InfoSource does not provide any data.
In delta mode, data requests with InfoSource 0FI_AR_4 and InfoSource 0FI_AP_4 do not provide any data if no new extraction has taken place with InfoSource 0FI_GL_4 since the last data transfer. This ensures that the data in BW for Accounts Receivable and Accounts Payable Accounting is exactly as up to date as the data for General Ledger Accounting.
Because in the source system delta extraction is based on CPU Time, the deltas are fetched once per day.
So if the source system delta extraction is to be achieved for the timely base, the same data can be pulled into BW easily by a process chain.
However, you can change this standard delivery. For more information, see note 485958.
Solution
It can be achieved by changing the settings at back end in the source system.
As the requirement is to get the deltas for every 30 minutes (1800 Secs), it needs to be update in the table BWOM_SETTING. We need to create an entry or change the existing entry for the field/Param_Name BWFINSAF with value 1800 (secs).
So now the Delta pointer for the datasource will be set to for every 30 mins, So that new deltas are created in source system.
Coming to BW side, we need to schedule the start variant in the process chain for every one hour ot two hours, depending on the time it takes for completion of the chain. So now the latest FI GL data can be reported.
So after loading the data into the cubes, the Bex queries will be able to fetch the latest financial data in the report output. Even the business object reports, OLAP universes based on the Bex queries will fetch the latest FI data and show the same data for the BO reports such as WebI or crystal reports based on the BO Universe.
http://scn.sap.com/people/ravikanth.indurthi/blog/2012/01/02/delta-extraction-for-0figl04-for-every-30-minutes
http://www.top-consultant.com/articles/sap%20bw.pdf