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
DELETE FROM titles_test
WHERE NOT EXISTS (
SELECT 1
FROM (
SELECT emp_no, MIN(ID) as min_id
FROM titles_test
GROUP BY emp_no
) as subquery
WHERE subquery.emp_no = titles_test.emp_no AND subquery.min_id = titles_test.ID
);