I am building the dimensional model for a data warehouse (as an exercise for a mini-course I am doing) and I want to build an aggregate to speed up queries.
Basically, I want the aggregate to group by:
(PizzaType), (Size), (Month), (Year)
I would have
num_pizza_types * num_sizes * num_months * num_years aggregate rows. One row for all combinations of that. But how does this change my dimensional model (or aggregate schema, I suppose)? How is this represented in the dimensional model? Do I remove all columns except month/year from my Date dimension? Do I remove all columns except Size and PizzaType from my Pizza dimension?