Fan trap

building semantic layer
1

Hi,

I am newbie in BO. i couldnt understand properly fan traps. I have read most of the threads related to fan traps and Dave blog. I partially understood the reason behind fan traps but struggling to resolve .

Can anybody explain to resolve a fan trap by using e-fasion universe so that i can practice the same example in my PC please.

Thanks in advance

Regards
krish

kris2727 (BOB member since 2010-07-28)

2

1.Create an alias for the table that is producing the multiplied aggregation.
2.Create a one to one join between the original table and the alias table.
3.Build the object that is causing the aggregation on the alias tables.
4.Define a context for the original table and a context for the alias.
5.Select File>Parameters and click the SQL tab to display the SQL page.
6.Select the Multiple SQL Statements for Each Measure checkbox.
7.Modify the select statement for the columns that are summed so that the columns in the alias table are summed and not the columns in the original table.

surya_sudheer :india: (BOB member since 2006-11-01)

3

Hi,

Have you read this entry in the Designer’s FAQ?

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

4

Hi Marek.

Thanks for your reply. Sorry to be pain but can you please explain fan trap by using e-fashion and with solution if possible.

i have read those threads and found same solution which is right. But im not able to implement that when i trying to resolve on my own.

Regards
kris

kris2727 (BOB member since 2010-07-28)

5

Not sure how else I should describe it than what I have already done:

And a good explanation of a fan trap by Andreas:

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