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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硅酸盐水泥的终凝时间不得长于()。
A. 6.5h
B. 7.5h
C. 8.5h
D. 10h
客户应及时为零售户提供库存建议,使安全(合理)库存保持在多长时间?
违反《治安管理处罚条例》的行为属于()
A. 犯罪行为
B. 违法行为
C. 违纪行为
D. 违章行为