如何在MySQL中執行存儲在變量中的查詢？

Question

我試圖執行在SQLyog的這是

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

查詢，但它給出了一個錯誤

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，如何能我會擺脫....

Answer 1

你是缺少prepare語句來執行動態查詢。

// your transfer variable query ... 

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