I'm currently designing a new tabular model which contains sales data. The sales data is received at a low level hierarchically speaking (Day, Store, SKU). The reports for this dataset however are not required at such a low level. The requirement is to view the data by month, county and product group.
Should I aggregate the data in the fact table to month, county and product (using a view or a SQL statement) or should I allow tabular to use the hierarchies in the warehouse to aggregate the data?
Any advice would be appreciated.