By Dr. Berg
Keeping current with Fix-Packs and SupportPacks for SAP BusinessObjects XI-3.1 has been a challenge for many companies. Some are simply waiting for BI-4.0 and have given up keeping their system current. That is a mistake.
For example, in March 2010, SAP provided a new WebI feature called "Query Stripping" in a special release of FixPack 1.9 to select customers. This is a very important performance and simplification feature for WebI that is worth taking a look at.
WebI Performance Problems
First, we have to understand the basics on how WebI work. For example, in a typical BW environment, we create BEx queries that are exposed to MDX and we build BOBJ universes one-for-one based on the BEx Query. The universes are then accessed by WebI queries. This results in the XI-3.1 server being uses as a 'pass-through' for the BEx Query that runs inside BW.
Since the fields in the BEx query and the universe are identical, we have two options. First, we can make a broad BEx query that can provide a lot of fields to the universe. This gives the WebI users a high degree of flexibility and it makes it easy to access and find data. However, it also means that every time a WebI query runs, the BEx query pulls all fields to the XI server, even when most of the fields are not included in the WebI query. The broad universe approach therefore creates significant performance issues.
A second choice is to create many smaller universes. However, this means dozens of BEx queries and universes, which are harder to navigate for end users. It al
so results in significantly more development and maintenance efforts for the organization.
The Query Stripping Solution
To solve this issue, SAP found a solution in 'query stripping'. This approach simply removes all fields that are not in the result set of the WebI query before the request is sent to BEx. So now we can have broader and fewer universes with minimal performance impact. The fields not wanted are simply grayed out in the WebI interface. If a user wants to add them to his ad-hoc query, he selects it and refreshes the report. The best of both worlds...
'Query Stripping' in Service Pack-3
As I said before, "query stripping" was included in Fix-Pack 1.9 for select customers, but not included in SP-2. Instead it was shipped as part of SP-3 in the summer of 2010, with several other options. Since many customers had not budget for a regression testing, they simply did not implement SP-3. That has been an unwise strategy.
It is true that SP-3 included many other features such as two new servers for Xcelsius, changes to the use of WebServices for Crystal reports, and changes in the way it ranked dimensions in WebI queries. In addition, it first appeared that SAP no longer supported MS server 2003. But that was not entirely true.
In SP-3, you can either apply it as a custom update or as a refresh install. If you do the refresh install, all changes above occurs, but if you do the update method, many of the changes are not required (i.e. servers and new operating system).
So, with SP-3 available for almost a year and FixPack 3.5 already here, there is no need to wait for BI-4.0. Just spend 25-30 minutes per box and get some more speed out of your WebI queries.
Do not continue to build hundreds of universes or do work-arounds. Most of this
work will be wasted. Instead keep current on service packs and fix packs and implement a formal update strategy. It is not unreasonable to plan for quarterly updates that are automatically applied by the basis team. The same will hold true for BI-4.0. If you don't have a formal FP and SP strategy, now is a great time to write one.
Next time I will explore the lessons learned from BW 7.3 that is scheduled for general release next Monday (May 30th). Meanwhile, give query stripping a try...