单选题Given that tables T1 and T2 contain the following rows: Table T1: C1 C2 1 4 1 3 1 2 Table T2: C1 C2 1 1 1 2 1 3 Which of the following queries will return only those rows that exist in both T1 and T2?（）ASELECT * FROM t1 UNION SELECT * FROM t2BSELECT * FROM t1 UNION DISTINCT SELECT * FROM t2CSELECT * FROM t1 INTERSECT SELECT * FROM t2DSELECT * FROM t1 WHERE (c1,c2)= (SELECT c1,c2 FROM t2)
单选题
Given that tables T1 and T2 contain the following rows: Table T1: C1 C2 1 4 1 3 1 2 Table T2: C1 C2 1 1 1 2 1 3 Which 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)
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