SELF-CHECK
Orders total 2000 and linked refunds 200. A join returns gross 4000. What is your first concern?

REFERENCE REASONING
Possible join fan-out. Inspect row grain and key cardinality before subtracting refunds; the intended net total under the stated case is 1800.

This is a reasoning reference for the supplied fictional case, not an executed app or tested cloud deployment. Alternative approaches are valid when supported by stated assumptions and evidence.
