Custom Aggregation Functions like SUM, AVERAGE etc.

Hi,

I want to write a custom aggregation function called PRODUCT (as it exists in Excel) to be used with [Measures].[Monthly Return] column. I could not see such function in AggregateFunction attribute of the mesaure in the Cube explorer.

What are the different ways I can write my own Aggregation functions? OR Achieve similar functionality with any alternative approach?

Appreciate your response.. let me know if further information is required.

-Ashish

You can't write your own Aggregation functions but you can certainly achieve the same result using MDX Script assignments to control how measures roll up. Regarding your specific problem, there is a function in the Analysis Services Stored Procedure project which does exactly what you're looking for:

http://www.codeplex.com/Wiki/View.aspx?ProjectName=ASStoredProcedures&title=Multiplication

...although my understanding is that using a sproc in your MDX Script could have an adverse effect on caching, so you might want to test out using the sproc and the technique using logs which is described by Darren Gosbell here:

http://geekswithblogs.net/darrengosbell/archive/2006/07/18/85539.aspx

HTH,

Chris