Data growth belongs to the top challenges for SAP BW administrators. For a long term success, strategic approach to data management is inevitable. However, there are few hints for BW administration that can instantly keep the data growth under control.
Have you checked what are the ten largest tables in your SAP BW lately? I would bet that if you go into the DB02 transaction now and check the largest tables in the system you will definitely find tables there, which you wouldn’t expect to be there.
Our research in over 300 BW systems worldwide (Fitness Test for SAP) shows that in 87 % of the cases at least one of the statistics tables in the system is part of the largest 10 tables in the system. Either in raw form in a RS table or in a TCT cube.
These are the good places to start if the data growth in your SAP BW is giving you headache:
1. Clean up RS* tables
For many RS* tables there are standard cleanup reports, which can be found in SAP Notes. For the cleanup of the table RSBATCHDATA table (this is usually the larges one) go here: SAP Note
You might not be able to delete all data wildly because some data in RS tables is used for operations within the system. Uprfront analysis is always a good idea, either internally or by an expert, if needed.
2. Delete old data from the technical content
The Technical Content in the TCT namespace contains the statistics data in a reportable manner. These cubes will grow, if not treated correctly. To delete data from them just perform a selective deletion, as you would do for a standard cube. Or, if you have NearLine Storage in place, just archive the older data into your NLS. Since it is still available for reporting, you can do this quite aggressively. You must remember however, that the NLS is write protected, so make sure the update of the TCT content from the statistic tables and the archive horizon aren’t set up in a way, that the load will fail, because you are loading into a already archived zone of the cube.
Repetition makes the master they say. To make sure you dont go back in a year and find those tables in the top ten largest tables don’t forget to perform these tasks regularly and so master your BW system. SAP standard tools provide you with advice for manual administration of housekeeping tasks. For bigger landscape, automation of such activities might be a good idea.