数据库中怎么统计人数数量
网站编辑2023-07-03 15:18:57177
SELECT column1, column2, COUNT(*) AS num_people
FROM (
SELECT num_people,
GROUP BY column1,
HAVING COUNT(*) > 100
) as people
WHERE people = (
SELECT num_people,
GROUP BY column2,
HAVING COUNT(*) > 100
);
在上面的示例中，SELECT column1, COUNT() as people 和 GROUP BY column2, HAVING COUNT() > 100 是用来统计人数的列，GROUP BY column2 是用来从表格中找到所有人数的行，HAVING COUNT(*) > 100 是用来统计所有人数的列。如果想要更加精确地统计人数，可以在表格中加入筛选条件，如 SELECT numpeople FROM students WHERE studentid = 100 来筛选学生。
