如何寫「創建用戶？」使用MySQL準備好的語句

Question

我想：

SET @user = 'foo@localhost'; 
SET @pass = 'bar'; 
SET @sql = 'CREATE USER ? IDENTIFIED BY ?'; 
PREPARE stmt FROM $sql; 

，我得到錯誤

ERROR 1064 (42000): 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 '? IDENTIFIED BY ?' 

我也嘗試過多種變體如何定義變量，但還是沒有任何的運氣。

SET @user = "'foo'@'localhost'"; 
SET @sql = 'CREATE USER ? IDENTIFIED BY ?'; 

甚至

SET @user = 'foo'; 
SET @host = 'localhost'; 
SET @sql = 'CREATE USER ?@? IDENTIFIED BY ?'; 

相當類似的問題已經被問2年多前，但仍然沒有有用的答案:( Create User with MySQLi Prepared Statement

Answer 1

這是唯一的出路如何我成功地創建一個用戶，遺憾的是它並沒有使用佔位符用戶變量：

SET @user := 'foo'; 
SET @host := 'localhost'; 
SET @pass := 'bar'; 
SET @sql := CONCAT("CREATE USER ", QUOTE(@user), "@", QUOTE(@host), " IDENTIFIED BY ", QUOTE(@pass)); 
PREPARE stmt FROM @sql; 
EXECUTE stmt; 

P.S. {CREATE | RENAME | DROP} USER語句應該是您使用的編程語言從MySQL 5.1.12