Best Practices on business logic placement in semantic layer, cognos fm model

[karthik.cognos]

Hi,
I'm looking for some Best Practices on where to have business logic placed...i.e in semantic layer in database versus cognos fm model versus cognos reports...Could you please let me know your thoughts?
If possible, could you please provide the source of the information you are providing (for example: wikipedia, white papers, blogs etc...)?

Thanks,
KC

[bdbits]

I do not have source documents other than some of it is likely in the FM guide.

The last place you want business logic is in individual reports. The biggest reason is simple - if business rules change (as they always eventually do), you would have to open every affected report and make the changes there. This is clearly undesirable.

Between database and FM model: If you put it in FM and want to consume the data with another tool, you have to reproduce the logic in that other tool. A database implementation can be more difficult, and will likely involve views and perhaps stored procedures, which are not always easily surfaced in a lot of tools. On the other hand, maybe your database has only been created for Cognos. I think it is easier to maintain in FM, as long as you are only going to use it with Cognos.

That's my two cents worth. Or twopence. Or whatever is a small amount in your local currency.