问题

Given that tables T1 and T2 contain the following rows:Table T1: C1 C2 1 4 1 3 1 2Table T2: C1 C2 1 1 1 2 1 3Which of the following queries will return only those rows that exist in both T1 and T2?()

Given that tables T1 and T2 contain the following rows:Table T1: C1 C2 1 4 1 3 1 2Table T2: C1 C2 1 1 1 2 1 3Which of the following queries will return only those rows that exist in both T1 and T2？()

A.SELECT * FROM t1 UNION SELECT * FROM t2

B.SELECT * FROM t1 UNION DISTINCT SELECT * FROM t2

C.SELECT * FROM t1 INTERSECT SELECT * FROM t2

D.SELECT * FROM t1 WHERE (c1,c2)= (SELECT c1,c2 FROM t2)

参考答案

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