Mahoor13

此函数根据输入长度和允许的字符生成一个随机字符串,如下所示:

SELECT str_rand(8, '23456789abcdefghijkmnpqrstuvwxyz');

功能代码:

DROP FUNCTION IF EXISTS str_rand;

DELIMITER //

CREATE FUNCTION str_rand(
    u_count INT UNSIGNED,
    v_chars TEXT
)
RETURNS TEXT
NOT DETERMINISTIC
NO SQL
SQL SECURITY INVOKER
COMMENT ''
BEGIN
    DECLARE v_retval TEXT DEFAULT '';
    DECLARE u_pos    INT UNSIGNED;
    DECLARE u        INT UNSIGNED;

    SET u = LENGTH(v_chars);
    WHILE u_count > 0
    DO
      SET u_pos = 1 + FLOOR(RAND() * u);
      SET v_retval = CONCAT(v_retval, MID(v_chars, u_pos, 1));
      SET u_count = u_count - 1;
    END WHILE;

    RETURN v_retval;
END;
//
DELIMITER ;

此代码基于 shuffle string function 由“罗斯·史密斯二世”发送