Question

我正在尝试创建一个具有INT参数并返回管理员名称的VARCHAR的函数。

这是我最近尝试过的代码：

DELIMITER //
CREATE FUNCTION `SHOW_ADMIN`(`PID` INT(11)) RETURNS VARCHAR(50)
NOT DETERMINISTIC CONTAINS SQL SQL SECURITY DEFINER
BEGIN 
DECLARE @retval VARCHAR;
SELECT NAME INTO @retval
FROM ADMINS WHERE ID = `PID`;
RETURN @retval; 
END//
DELIMITER ;

注意：上面的代码基本上是从“添加例程” GUI复制粘贴。

我尝试过的其他代码：

DELIMITER //
CREATE FUNCTION SHOW_ADMIN(PID INT) RETURNS VARCHAR
BEGIN
    DECLARE @retval VARCHAR;
SELECT NAME INTO @retval
FROM ADMINS WHERE ID = PID;
RETURN @retval;
END//
DELIMITER ;

当前代码显示的错误显示：

1064 - You have an error in your SQL syntax;
check the manual that corresponds to your MariaDB 
server version for the right syntax to use near 
'@retval VARCHAR;
SELECT NAME INTO @retval
FROM ADMINS WHERE ID = `PID`' at line 4

代码最初来自：MySQL, create a simple function

编辑：

How to declare a variable in MySQL? 不介绍在函数上下文中如何使用它，而是：MySQL select in function。

Answer 1

设法找到一个解决方案，它与MySQL select in function

重复

无论如何，这解决了我的问题。

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error:14077410:SSL routines:SSL23_GET_SERVER_HELLO:sslv3 alert handshake failure
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具有int参数的函数并返回varchar会导致SQL语法错误＃1064

1 个答案: