問題文
An analyst combines a row-level calculation [Price] * [Quantity] with SUM in one field: SUM([Price] * [Quantity]). Is this valid, and what does it compute?
選択肢
- It fails because it mixes aggregate and non-aggregate values, and the multiplication has to be wrapped in its own aggregate first.
- It computes SUM(Price) times SUM(Quantity).
- It is valid: the row-level multiplication is computed per row, then summed, giving total revenue across rows.
- It is invalid because you cannot multiply two fields.