Sometimes you'll want to see data from the source code dictionary — like Acquisition Cost, etc, with statistics gathered over the course of a date range (like revenue, or spend). The challenge is that the source code dictionary information spans ALL dates ... so when you join them together it appears to generate duplicate rows. For example, with this Dictionary:
And with this set of statistics by date:
When we join information from these two tables, by the source code, you can see the acquisition cost appears for EVERY instance of the date. So if you try to SUM that field, it's not going to do what you want.
JOINED table — Dictionary + Statistics = Source Code Summary By Date
Alternatively, using things like MIN(acquisition_cost) can avoid this issue.