Help to Solve on to many relationship involving measure

[system]

I have a fact table Defetcts and a dimension table AssetImpacted having one to many relationship.Foreach defect in fact table I can have many assets impacted in dimension table.Also I have a measure in fact table giving a total count of assets impacted.When i join these to tables the count of assets get duplicated(multiplied).I have given the scenario below

Defects table:

DefectId DefectName AsstsImpacted
1002 bug 2

Assetsimpacted Table:

DefectId AssetID AssetName
1002 201 PC
1002 202 Laptop

when i retrive a report involving the two tables to show a arregated Asset impacted count ,I get it 4.

Defectid AsetImpacted
1002 4

Thi is because of the cartesion join.

Any help on how to handle it at universe level.

I also have other table whch have one to many relationship with fact table.

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sagarrane10 (BOB member since 2010-11-08)

[system]

Welcome to B:bob:B!

The problem that you are experiencing is called a fan trap. It’s described here:

FAQ: Designer

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…

You can find the resolution of the fan trap there too.

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Marek Chladny (BOB member since 2003-11-27)

[system]

ok…Thanks for the help

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sagarrane10 (BOB member since 2010-11-08)