mysql - SQL 语法错误 1064

Question

我有一个语法错误，我一直试图修复它，但我无法弄清楚。错误表明附近有问题

'SET result = CONCAT(result,charac); END IF; SET indexchar = indexchar+1;'

我正在尝试创建的完整功能:

DELIMITER //
DROP FUNCTION IF EXISTS `alphabet`;
CREATE FUNCTION `alphabet` (serial_number CHAR, name VARCHAR(100)) RETURNS VARCHAR(50) 
DETERMINISTIC
BEGIN
    DECLARE result VARCHAR(40) DEFAULT '';
    DECLARE stringalpha VARCHAR(50) DEFAULT 'abcdefghijklmnopqrstuvwxyz0123456789';
    DECLARE indexchar int DEFAULT 1;
    DECLARE charlength INT;
    DECLARE charac CHAR(1);

    SET charlength = CHAR_LENGTH(stringalpha);

WHILE indexchar <= charlength DO
    SET charac = SUBSTRING(stringalpha,indexchar,1);
    IF (serial_number LIKE CONCAT('%',charac,'%') OR name LIKE CONCAT('%',charac,'%'))
        SET result = CONCAT(result,charac);
    END IF;
    SET indexchar = indexchar+1;
END WHILE

RETURN result;
END //
DELIMITER ;

我尝试编写但没有成功:

SET result = CONCAT('result','charac');

Answer 1

DROP FUNCTION IF EXISTS `alphabet`;
DELIMITER //
CREATE FUNCTION `alphabet` (serial_number CHAR, name VARCHAR(100)) RETURNS VARCHAR(50) 
DETERMINISTIC
BEGIN
    DECLARE result VARCHAR(40) DEFAULT '';
    DECLARE stringalpha VARCHAR(50) DEFAULT 'abcdefghijklmnopqrstuvwxyz0123456789';
    DECLARE indexchar int DEFAULT 1;
    DECLARE charlength INT;
    DECLARE charac CHAR(1);

    SET charlength = CHAR_LENGTH(stringalpha);

WHILE indexchar <= charlength DO
    SET charac = SUBSTRING(stringalpha,indexchar,1);
    IF (serial_number LIKE CONCAT('%',charac,'%') OR name LIKE CONCAT('%',charac,'%')) THEN
        SET result = CONCAT(result,charac);
    END IF;
    SET indexchar = indexchar+1;
END WHILE; -- ********************** missing semi

RETURN result;
END //
DELIMITER ;

缺少THEN，END WHILE后缺少分号，顶部分隔符位于错误的行