【mysql】关于循环插入数据 存储设计

要求插入的数据有一定的规律

 新建实例列表
 CREATE TABLE    users
 (
   userId                    INT(11) NOT NULL,
  userName               VARCHAR(255)  NOT NULL,
 Serves                  INT(11)  NOT NULL,
 PRIMARY    KEY   (userId)
 );

 创建存储过程 例如：随机写入5000条数据

 begin
   declare i int default 1;
   start transaction;
    while i<=5000 do
     insert into users(userId,userName,Serves) values(i,concat('z00',i),123);
     set i=i+1;
    end while;
   commit;
  end

设置随机函数取前几条

select * from users order by rand() LIMIT 3 ;

　　

users表刚才插入5000条数据

SELECT * FROM users
WHERE userId >= (
(SELECT MAX(userId) FROM users WHERE userId >= '')-
(SELECT MIN(userId) FROM users WHERE userId<= '')
) * RAND() + (SELECT MIN(userId) FROM users  WHERE userId <= 65)
 LIMIT 5

那么上面的随机取五条可以换算成

SELECT * FROM users
WHERE userId >= (5000-1)*rand()+1
limit 5