While helping my customer to switch to latest BW version, we have come across Advanced DSO (aDSO), the new Infoprovider type introduced by SAP in BW 7.4 on HANA. This blog summarizes the FAQs on advanced DSO.
What is SAP BW advanced DSO?
In all current and previous versions of BW, transaction and summary data are stored in ‘InfoProviders’. All reports in presentation layer, e.g. BW workbooks, BO Webi, Dashboard, read information from Infoproviders via BEx Queries.
Starting from BW 7.4 SP10, SAP introduces the new InfoProvider type, Advanced DSOs. Advanced DSO will replace PSA, DSO (Referred now as Classic DSO), and InfoCube.
It is SAP intentions to simplify the BW flow that are too complicated for customers to understand in current version.
Is it a must to switch to aDSO?
No. Our customer has upgraded to BW 7.5 on HANA and they are still comfortably using all the existing InfoProviders without any problems.
However, in the latest version of BW, BW/4 HANA, existing Infoprovider types could not be used and must all be converted to aDSO.
In other words, if you are not going to upgrade to BW/4 HANA, there is absolutely no need to convert your existing flow to use aDSOs.
Any advantages to use aDSO?
According to SAP, the ETL performance and reporting performance would be much faster for aDSOs. Actually we have tested it.
For ETL performance, we have tested the response time of a Data Transfer Process (DTP) from a DSO to an InfoCube and Advanced DSO respectively, all other settings unchanged. The DTP to aDSO has improved significantly. To load 10 million records, the original time is 50 minutes. After switching to aDSO, the run time is 3 minutes, about 17 times faster.
For reporting performance, we use a BW workbook to connect to InfoCube and aDSO respectively. The BW workbook reads 600,000 cells and there is no difference in response time at all. To our understanding, BW reporting using Analysis for Office (AO) do have improvements, but not the conventional BW workbook.
Any Issues to switch to aDSO?
Conversion to aDSO involves a lot of overhead, and there is no easy way to automatically convert a classic Inforprovider to aDSO, which means:
- All BW queries that read the class InfoProvider would be obsoleted. New queries need to be created so that it would read from aDSO.
- Customer usually uses only one query for all BW workbooks. For example, our customer has 200+ BW workbooks and they all use 1 BW query to read the InfoProvider. What it means it that all 200+ BW workbooks must be copied out and changed to use the new query that read from aDSO.
- In the ETL layer, the same issue exist. As the number of ETL process is manageable, it is easier for developer to create new ETL process and process chains for aDSO, to replace the current ETL process.
SAP did provide a utility called RSB4HRTF to help customer to convert classic Infoproviders to aDSO. We will examine the utility in next blog.