system
February 21, 2013, 3:21pm
#1
Hi guys so my Universe is complete and when I am executing reports I am getting inaccurate result any suggestions how to tackle this issue. Basically user has 15 Apps under their name the report shows 18, another user has 4 Apps and the report shows 7 Apps under that user name. Any suggestions would be appreciated.
Thanks!!!
AK110 (BOB member since 2012-06-25)
system
February 21, 2013, 3:25pm
#2
Hi,
You might experience a fan trap or a chasm trap in your universe.
Have you checked whether they are there in the universe and solved them properly?
Marek Chladny (BOB member since 2003-11-27)
system
February 21, 2013, 3:37pm
#3
I am kinda new to this and working on 4.0so what’s the best approach I can take to detect fan trap and chasm trap?
AK110 (BOB member since 2012-06-25)
system
February 21, 2013, 3:41pm
#4
First you need to understand what those traps are and why they cause problems.
Fan trap:
What is a fan trap, why is it a problem, and how do I resolve it?
Dave Rathbun describes it well in his presentation, ZEN and the ART of Universe Design. Which is located here: http://www.dagira.com/conference-presentations/
Here is a quick synopsis of Fan Trap from his presentation:
A Fan Trap is a one - many - many relationship. This would happen if you are using a Summary and a Detail table in one query. Fan Traps can cause numbers to multiply. Business Objects resolves this t…
Chasm trap:
What is a chasm trap, why is it a problem, and how do I resolve it?
Business Objects describes it best at this web site: http://tips.businessobjects.com/tips/unvdes/tip/ut001/ut001.htm
The Chasm trap occurs when two “many to one” joins converge on a single table. It is a one - many - one relationship. You will get incorrect results when the following circumstances exist:
A “many to one to many relationship” exists among three tables in the universe structure. The query includes obje…
Use also search to find those many topics where fan and chasm traps were discussed in the past.
Marek Chladny (BOB member since 2003-11-27)