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以下SQL语句中,哪一个能正确统计每个城市的人口数量?

题目配图
A.SELECT city, COUNT(*) FROM population_table GROUP BY city
B.SELECT city, COUNT(*) FROM population_table ORDER BY city
C.SELECT city, SUM(*) FROM population_table GROUP BY city
D.SELECT city, SUM(population) FROM population_table ORDER BY city

优质解答

答案

A

解析

COUNT(*)用于计数,GROUP BY city可对每个城市进行分组,因此A是正确选项。

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