无法在 MYSQL 中创建函数错误 1064 (42000)

Question

你好，我正在使用 MySQL 创建一个函数：

CREATE FUNCTION INSERTGROUP(name VARCHAR(50))
RETURNS INT
NOT DETERMINISTIC
BEGIN
DECLARE 'idGroup' INT;

IF (NOT EXISTS (SELECT groupID FROM groupsTable WHERE groupName = 'name'))
THEN INSERT INTO groupsTable (groupName) VALUES ('name');

SELECT groupID INTO 'idGroup' FROM groupsTable WHERE groupName='name';

RETURN 'idGroup';
END//

但是当我尝试创建它时出现此错误：

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
''idGroup' INT;

IF (NOT EXISTS (SELECT groupID FROM serverGroupsTable WHERE gro' at line 5

我已经浏览过论坛和其他与此类似的问题，但我无法让它创建该功能。

我做错了什么？语法正确吗？我还需要添加其他东西吗？

好的，这就是我尝试过的：

CREATE FUNCTION INSERTGROUP(name VARCHAR(255))
RETURNS INT
NOT DETERMINISTIC
BEGIN
DECLARE idGroup INT;

IF (NOT EXISTS (SELECT groupID FROM groupsTable WHERE groupName = name))
THEN INSERT INTO groupsTable (groupName) VALUES (name);

SELECT groupID INTO idGroup FROM groupsTable WHERE groupName=name;

RETURN idGroup;
END//

和

CREATE FUNCTION INSERTGROUP(name VARCHAR(255))
RETURNS INT
NOT DETERMINISTIC
BEGIN
DECLARE idGroup INT;

IF (NOT EXISTS (SELECT groupID FROM groupsTable WHERE groupName = 'name'))
THEN INSERT INTO groupsTable (groupName) VALUES ('name');

SELECT groupID INTO idGroup FROM groupsTable WHERE groupName='name';

RETURN idGroup;
END//

对于最后两个我得到这个错误：

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
'' at line 13

和上面的类似

我也做DELIMITER //改变它;

Answer 1

从声明中删除引号

DECLARE idGroup INT;

并且您忘记了函数开头的分隔符更改

delimiter //
CREATE FUNCTION INSERTGROUP(name VARCHAR(255))

你忘了结束你的if发言

end if;

无论你希望它在哪里结束