DBI202Xuất hiện trong 1 đề thi
Suppose relation $R(A, B, C)$ has the following tuples: | A | B | C | | :--- | :--- | :--- | | 1 | 1 | 3 | | 1 | 2 | 3 | | 2 | 1 | 4 | | 2 | 3 | 5 | | 2 | 4 | 1 | | 3 | 2 | 4 | | 3 | 3 | 6 | Which tuple is contained in the result of the following query: ```sql SELECT A, COUNT(DISTINCT B) FROM R GROUP BY A HAVING SUM(B) > 3; ```
Các lựa chọn
A$(3, 7)$
B$(3, 12)$
C$(2, 10)$
D$(2, 3)$