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  • Bruno Antonio thinks this is interesting:

In the orders pipeline fact table, assume you have 10 basic fundamental quantity facts, in addition to five units of measure. If you physically store all the facts expressed in the different units of measure, you end up with 50 (10 ×5) facts in each fact row. Instead, you can compromise by building an underlying physical row with 10 quantity facts and 4 unit-of-measure conversion factors. You need only four conversion factors rather than five because the base facts are already expressed in one of the units of measure. The physical design now has 14 quantity-related facts (10 + 4), as shown in Figure 6.20. With this design, you can see performance across the value ch...