如何在MySQL中执行存储在变量中的查询？

Question

我试图执行在SQLyog的这是

SET @adm_code = 12781; 
SET @transfer = (SELECT MAX(id) FROM std_transfer_history AS sth 
WHERE admission_code = @adm_code); 
EXECUTE @transfer; 

查询，但它给出了一个错误

Query: execute @transfer 

Error Code: 1064 
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '@transfer' at line 1 

Execution Time : 0 sec 
Transfer Time : 0 sec 
Total Time  : 0 sec 

因此，如何能我会摆脱....

Answer 1

你是缺少prepare语句来执行动态查询。

// your transfer variable query ... 

PREPARE stmt FROM @transfer; 
EXECUTE stmt; 
DEALLOCATE PREPARE stmt;