报错情况如下：Invalid Stored Procedure Syntax出现无法保存的问题，由于之前没怎么用过函数模块

Question

navicat写过程或者函数，出现这种情况是什么情况

DELIMITER //  
CREATE FUNCTION `SelectData`()  
BEGIN  
    DECLARE done INT DEFAULT FALSE;  
    DECLARE table_name VARCHAR(255);  
    DECLARE cur CURSOR FOR SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = 'db_kakou' AND TABLE_NAME LIKE 'all_data%';  
    DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;  
      
    OPEN cur;  
    read_loop: LOOP  
        FETCH cur INTO table_name;  
        IF done THEN  
            LEAVE read_loop;  
        END IF;  
        SET @query = CONCAT('SELECT * FROM ', table_name, ' WHERE HOUR(pass_time) >= 7 AND HOUR(pass_time) < 9');  
        PREPARE stmt FROM @query;  
        EXECUTE stmt;  
        DEALLOCATE PREPARE stmt;  
    END LOOP;  
    CLOSE cur;  
END //  
DELIMITER ;

报错情况如下：
Invalid Stored Procedure Syntax
出现无法保存的问题，由于之前没怎么用过函数模块，所以不是很了解这是什么情况，求解！！

Answer 1

语法使用错误了