1 不按照顺序查询

SELECT * FROM person_info WHERE birthday = ‘1990-09-27’;

2 ASC和DESC混用

SELECT * FROM person_info ORDER BY name, birthday DESC LIMIT 10;

3 非前缀匹配

SELECT * FROM person_info WHERE name LIKE ‘%As%’;

4 排序列不包括索引列

SELECT * FROM person_info ORDER BY name, country LIMIT 10;

5 索引列上有计算

SELECT * FROM person_info WHERE DATEDIFF(birthday,’1990-09-27’)=0；

6 范围查询之后的列

SELECT * FROM person_info WH

7 order by 两次以上，升降序不统一

8 a，b，c的索引 等值和in可以乱序，必须满足顺序