如何在PROCEDURE MySQL的CONCAT（）中使用UPDATE

Question

我嘗試通過PROCEDURE更新存在表。 但是我收到一個錯誤：MySQL：＃1064-您的SQL語法有錯誤； 檢查與MySQL服務器版本相對應的手冊，以在第1行的'= iOS， phone_manufacture = Apple， phone_model = iPhone， os_vers = iOS XX'附近使用正確的語法

我的程序：

BEGIN 
DECLARE a, b INT;
DECLARE a1, a2, a3, a4 TEXT;
DECLARE cur1 CURSOR FOR SELECT id FROM z7_group;  
DECLARE CONTINUE HANDLER FOR NOT FOUND SET b = 1;  
OPEN cur1;   
SET b = 0; 
SET a1 = "iOS";
SET a2 = "Apple";
SET a3 = "iPhone";
SET a4 = "iOS X.X";
WHILE b = 0 DO  
FETCH cur1 INTO a;
IF b = 0 THEN
 SET @data_ all_group = (SELECT `myTables` FROM `all_group` WHERE id= a);
 SET @s = CONCAT('UPDATE ', @data_ all_group, 'SET `os` = ',a1,', `phone_manufacture` = ',a2,', `phone_model` = ',a3', `os_vers` = ',a4,');
 PREPARE stmt3 FROM @s;
 EXECUTE stmt3;
END IF;
END WHILE;
CLOSE cur1;
END;

Answer 1

您有兩種選擇：（還有更多選擇，但我認為這是您想要的）

1. 初始化時將值括在單引號中：

    SET a1 = "'iOS'"; SET a2 = "'Apple'"; SET a3 = "'iPhone'"; SET a4 = "'iOS X.X'"; 

   並修改句子：

    CONCAT('UPDATE ', @data_all_group, ' SET `os` = ',a1,', `phone_manufacture` = ',a2,', `phone_model` = ',a3,', `os_vers` = ',a4) 

   結果將是：

    UPDATE your_table SET `os` = 'iOS', `phone_manufacture` = 'Apple', `phone_model` = 'iPhone', `os_vers` = 'iOS XX' 

2. 或者：修復查詢版本：

     SET @s = CONCAT('UPDATE ', @data_all_group , "SET `os` = '" , a1 ,"'," , "`phone_manufacture` = '",a2,"'," , "`phone_model` = '",a3,"'," , "`os_vers` = '",a4,"'");