本文介绍下,mysql中case语句的一个例子,在存储过程中使用case when语句的参考示例,有需要的朋友,可以看看。
mysql> delimiter $$
mysql> CREATE PROCEDURE myProc(id int) //创建mysql存储过程
-> BEGIN
->
-> CASE
-> WHEN id < 2 THEN
-> select 'less than 2';
->
-> WHEN id > 2 and id < 5 THEN
-> select 'greater than 2 and less than 5';
->
-> WHEN id > 5 THEN
-> select 'greater than 5';
->
-> END CASE;
-> END$$
Query OK, 0 rows affected (0.00 sec)
mysql> delimiter ;
mysql> call myProc(2); //调用存储过程myProc
ERROR 1339 (20000): Case not found for CASE statement
mysql> call myProc(20);
+----------------+
| greater than 5 |
+----------------+
| greater than 5 |
+----------------+
1 row in set (0.00 sec)
Query OK, 0 rows affected (0.00 sec)
mysql> drop procedure myProc; //删除存储过程myProc
Query OK, 0 rows affected (0.00 sec)
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