题解 | #删除emp_no重复的记录
删除emp_no重复的记录,只保留最小的id对应的记录。
https://www.nowcoder.com/practice/3d92551a6f6d4f1ebde272d20872cf05
-- 删除emp_no重复的记录,只保留最小的id对应的记录
DELETE FROM titles_test
WHERE id NOT IN (
-- 子查询:选择每个emp_no分组中最小的id
SELECT min_id FROM (
SELECT MIN(id) AS min_id
FROM titles_test
GROUP BY emp_no
) AS t1
);

