Question on initial aggregation design

Hi, all experts here,

I have questions for the initial aggregation design and these questions are really important as part of the implementation of the cubes.

1. Before we launch the aggregation design wizard, we create user-hierarchies, after we process the cube, these user-hierarchies are then as the first initial aggregations? How can we evaluate the benefits and cost of these aggregations based on user-hierachies?

2. When we create initial aggregations with 'Aggregation design wizard', setting up the value for 'performance increase', how this fits into (work together with user_hierarchies?). Say, we set up the value for 'performance increase' as 30%, the initial user-hierarchies aggregations may not meet this goal, in this case, how the system works to meet this goal? Will it create other aggregations together with the user-hierarchies based aggregations? And where can we see these information? And how can we evaluate the aggregations after its design?

Thanks a lot and I think they are very very necessary for me to get these information and I think they are very very helpful. And I am looking forward to hearing from you shortly.

With best regards,

Yours sincerely,

Hi,

I am not to sure if I get the what you are asking, but the idea of aggregations is to help performance when querying the cube. So you should be able to test the benefits of any aggregation in the time it takes to retrieve the data. You are going to have to clear the cache as well when doing this, as the cache will probably play an adverse effect on your results if you don't.

If the performance is not met with the wizard i would suggest using the aggregation design tool and create your own that help specific queries you have. One aggregation may help improve one query but not others, and the wizard may not always get it right. It is a matter of trial and error, I would suggest using the profiler and see whether the queries you are running actually hit the aggregation or the partition. You can normally tell from the profiler where to start with the aggregations or even the queries themselves.

Hope that was some help, may have missed what you were asking

Cheers

Matt

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Hi, Matt,

Thanks a lot for the very helpful advices.

With best regards,

Yours sincerely,