MySQL生成随机数据

Question

在MySQL中，我需要一些表将电话号码和电子邮件地址随机化，以便为开发目的随机生成。

在MySQL中，我如何为电话号码生成7位唯一的随机数字？

如何生成像545165498@mailinator.com这样的随机电子邮件地址。

如何使用MySQL查询生成这些随机数据？

Answer 1

MySQL rand()在范围0 <= value < 1.0中返回一个随机浮点值.

乘以另一个数字：UPPER_BOUND并得到它的底部，您将得到0到(上限-1)之间的随机整数，如下所示：

SELECT floor(rand() * 10) as randNum;

这只会给你一个在0到10之间的随机数。

将10改为比您想要生成的值高的数字。

这样的东西:

UPDATE user 
SET email = CONCAT(FLOOR(rand() * 10000000),'@mailinator.com'), 
    PhoneNo = FLOOR(rand() * 10000000)

Answer 2

这会给你一个7位长度的随机数。

选择楼层(1000000+ RAND() * 8999999)

像这样的东西应该根据你的要求更新你的电话号码和电子邮件地址。

UPDATE Customers 
SET phone = CAST(FLOOR(1000000 + RAND(8999999) AS VARCHAR), 
email = CONCAT(CAST(FLOOR(1000000 + RAND(8999999) AS VARCHAR), '@mailinator.com')

Answer 3

MySQL生成随机数据演练：

随机数介于0(包括)和1排他性之间：

mysql> select rand();
+--------------------+
| rand()             |
+--------------------+
| 0.5485130739850114 |
+--------------------+                                                     
1 row in set (0.00 sec)

随机整数介于0(包含)到10排他之间：

mysql> select floor(rand()*10);
+------------------+
| floor(rand()*10) |
+------------------+
|                6 |
+------------------+
1 row in set (0.00 sec)

随机字母或数字：

mysql> select concat(substring('ABCDEF012345', rand()*36+1, 1));
+---------------------------------------------------------------------------+
| concat(substring('ABCDEF012345', rand()*36+1, 1))                         |
+---------------------------------------------------------------------------+
| F                                                                         |
+---------------------------------------------------------------------------+
1 row in set (0.00 sec)

随机字母a到z:

mysql> select char(round(rand()*25)+97);
+---------------------------+
| char(round(rand()*25)+97) |
+---------------------------+
| s                         |
+---------------------------+
1 row in set (0.00 sec)

随机8字符字母数字字符串：

mysql> SELECT LEFT(UUID(), 8);
+-----------------+
| LEFT(UUID(), 8) |
+-----------------+
| c26117af        |
+-----------------+
1 row in set (0.00 sec)

MySQL:中的随机大写字母

mysql> select CHAR( FLOOR(65 + (RAND() * 25)));
+----------------------------------+
| CHAR( FLOOR(65 + (RAND() * 25))) |
+----------------------------------+
| B                                |
+----------------------------------+
1 row in set (0.00 sec)

将随机行加载到表中：

mysql> create table penguin (id INT primary key auto_increment, msg TEXT);
Query OK, 0 rows affected (0.02 sec)

mysql> insert into penguin values (0, LEFT(UUID(), 8));
Query OK, 1 row affected (0.00 sec)

mysql> select * from penguin;
+------+----------+
| id   | msg      |
+------+----------+
|    0 | abab341b |
+------+----------+
1 row in set (0.00 sec)

加载随机行：

制作一个名为dennis的程序，将1000行随机行加载到企鹅中。

mysql> delimiter ;;
mysql> drop procedure if exists dennis;;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> create procedure dennis()
    -> begin
    -> DECLARE int_val INT DEFAULT 0;
    -> myloop : LOOP
    ->   if (int_val = 1000) THEN
    ->     LEAVE myloop;
    ->   end if;
    ->   insert into penguin values (0, LEFT(UUID(), 8));
    ->   set int_val = int_val +1;
    -> end loop;
    -> end;;
Query OK, 0 rows affected (0.00 sec)  

mysql> call dennis();;

mysql> select * from penguin;;
+------+----------+                      
| id   | msg      |              
+------+----------+                   
|    0 | abab341b |                 
|    1 | c5dc08ee |           
|    2 | c5dca476 |
...
+------+----------+

更新表中的所有行以具有随机数据：

mysql> create table foo (id INT primary key auto_increment, msg TEXT);
Query OK, 0 rows affected (0.02 sec)

mysql> insert into foo values (0,'hi');
Query OK, 1 row affected (0.00 sec)

mysql> insert into foo values (0,'hi2');
Query OK, 1 row affected (0.00 sec)

mysql> insert into foo values (0,'hi3');
Query OK, 1 row affected (0.00 sec)

mysql> select * from foo;
+----+------+
| id | msg  |
+----+------+
|  1 | hi   |
|  2 | hi2  |
|  3 | hi3  |
+----+------+
3 rows in set (0.00 sec)

mysql> update foo set msg = rand();
Query OK, 3 rows affected (0.00 sec)
Rows matched: 3  Changed: 3  Warnings: 0

mysql> select * from foo;
+----+---------------------+
| id | msg                 |
+----+---------------------+
|  1 | 0.42576668451145916 |
|  2 | 0.6385560879842901  |
|  3 | 0.9154804171207178  |
+----+---------------------+
3 rows in set (0.00 sec)