云计算学习路线图素材、课件，CASE的其他用法讲解

在本篇文章中将给大家讲解下CASE的其他用法讲解：

使用带有简单CASE函数和CASE搜索函数的select语句在select语句中，CASE搜索函数允许根据比较值

select

CASE

WHEN good_type

WHEN good_type>=2 AND good_type

THEN '>=2 &&

ELSE '>=3' END AS good_now_type,

good_type,user_id,user_name

FROM t_main_order;

+---------------+-----------+---------+-----------+

| good_now_type | good_type | user_id | user_name |

+---------------+-----------+---------+-----------+

|

|

|

| >=2 &&

| >=3 | 3 | 5 | fiww |

| >=3 | 3 | 6 | www |

| >=3 | 3 | 7 | wfiw |

+---------------+-----------+---------+-----------+

CASE的其他用法

select

CASE

WHEN good_type

WHEN good_type>=2 AND good_type

THEN '>=2 && =3'

END AS good_now_type,

count(*) AS num_count

FROM t_main_order

GROUP BY good_now_type

ORDER BY num_count;

+---------------+-----------+

| good_now_type | num_count |

+---------------+-----------+

| >=2 &&

|

| >=3 | 3 |

+---------------+-----------+