循环经典例题

#在stringcontent中添加 id 和content 然后加入随机字符
CREATE TABLE stringcontent(
id INT PRIMARY KEY AUTO_INCREMENT,
content VARCHAR(20)

);
DELIMITER $

CREATE PROCEDURE xxy(IN xxl INT)
BEGIN
DECLARE i INT DEFAULT 1;
DECLARE a VARCHAR(26) DEFAULT 'abcdefghijklmnopqrstuvwxyz';
DECLARE h INT DEFAULT 1;
DECLARE j INT DEFAULT 1;

WHILE i<= xxl DO

SET h =FLOOR(RAND()*26+1);
SET j = FLOOR(RAND()*(26-h+1)+1) ;
INSERT INTO stringcontent(content) VALUES(SUBSTR(a,h,j));
SET i=i+1;
END WHILE ;
END $