-- 查询年龄大于20岁的人，按性别分组，统计每组的人数，并只显示性别人数大于2的数据条数
Error:SELECT count(), from student WHERE age>20 GROUP BY sex HAVING count()>2;
SELECT ,count() from student WHERE age>20 GROUP BY sex HAVING count()>2;
count(*)问题
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转载自www.cnblogs.com/hellsino/p/11909303.html
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