如何在 MYSQL 中进行查询以
从表中选择People_id的总和,每 5 年按出生日期分组??
提前致谢
> http://sqlfiddle.com/#!9/644e2d/2
SELECT (YEAR(birthdate) - MOD(YEAR(birthdate),5)) as `year`,COUNT(id)
FROM users
GROUP BY `year`