Hi Jez,

Thanks for your answer. I guess there is no single best practice that satisfies everyone.

I will use the following guidelines:

- Try to add the fact based calculations to the fact tables, in order to avoid that users or applications can dispute the values.

- For the “soft-rules” use computed columns instead views or hardcode them in ETL packages. In this way if some definition slightly changes, no SSIS package needs to be adjusted and redeployed. If all of the needed columns for the calculations are included in the fact table, there are at least two options: 1) include these columns in the fact table, 2) use a view.

- Use computed columns with persisted values. I need to test the performance of writing in such a tables, but a data mart should be optimized for reading.