Question

我有一个名为Joined（varchar（50））的MYSQL列，其值例如13个数字如何实现该查询？

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Answer 1

您可以生成md（）随机字符串，例如：

UPDATE `users` 
SET `joined` = concat('153',SUBSTRING(MD5(RAND()) FROM 1 FOR 10) )

或

UPDATE `users` 
SET `joined` = concat('153',SUBSTRING(MD5(RAND()) FROM 1 FOR 6), 
                            SUBSTRING(MD5(RAND()) FROM 1 FOR 4) )

或者如果只需要数字就可以使用

UPDATE `users` 
SET `joined` = concat('153',CAST(rand()*1000000 as UNSIGNED), 
                            CAST(rand()*10000 as UNSIGNED) )

of对于带有短字符串的行，您可以在根据需要调整代码时使用

UPDATE `users` 
SET `joined` = case when length(joined)= 14 then
                concat('153',CAST(rand()*10000000 as UNSIGNED), 
                            CAST(rand()*10000 as UNSIGNED) )
                    when  length(joined)= 13 then
                concat('153',CAST(rand()*1000000 as UNSIGNED), 
                            CAST(rand()*10000 as UNSIGNED) )
                .....
                end

Answer 2

尝试：

UPDATE `users` 
SET `joined` = CONCAT('153', FLOOR(RAND()* 9000000000) + 1000000000)

MySQL-使用最后12位数字的随机值更新联接的列

2 个答案: