MySQL Generate Random Data - mysql

Question

In MySQL I have some tables I need to randomize the phone numbers and Email addresses to be randomly generated for development purposes.
In MySQL how could I generate 7 digit unique random numbers for the phone numbers?
How can I generate random email address like 545165498#mailinator.com.
How can I generate this random data with MySQL Queries?

Answer 1

MySQL rand() Returns a random floating-point value in the range 0 <= value < 1.0.
Multiply that by another number: UPPER_BOUND and get the floor of that, and you will get a random integer between 0 and (UPPER_BOUND-1) like this:
SELECT floor(rand() * 10) as randNum;
That will give you only one random number between 0 and 10.
Change the 10 to the number one higher than you want to generate.
Something like this :
UPDATE user
SET email = CONCAT(FLOOR(rand() * 10000000),'#mailinator.com'),
PhoneNo = FLOOR(rand() * 10000000)

Answer 2

This should give you a random number of 7 digits length
SELECT FLOOR(1000000 + RAND() * 8999999)
And something like this should update your phone numbers and e-mail addresses according to your requirement
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 Generate random data walkthrough:
Random number between 0 (inclusive) and 1 exclusive:
mysql> select rand();
+--------------------+
| rand() |
+--------------------+
| 0.5485130739850114 |
+--------------------+
1 row in set (0.00 sec)
Random int between 0 (inclusive) and 10 exclusive:
mysql> select floor(rand()*10);
+------------------+
| floor(rand()*10) |
+------------------+
| 6 |
+------------------+
1 row in set (0.00 sec)
Random letter or number:
mysql> select concat(substring('ABCDEF012345', rand()*36+1, 1));
+---------------------------------------------------------------------------+
| concat(substring('ABCDEF012345', rand()*36+1, 1)) |
+---------------------------------------------------------------------------+
| F |
+---------------------------------------------------------------------------+
1 row in set (0.00 sec)
Random letter a to z:
mysql> select char(round(rand()*25)+97);
+---------------------------+
| char(round(rand()*25)+97) |
+---------------------------+
| s |
+---------------------------+
1 row in set (0.00 sec)
Random 8 character alphanumeric string:
mysql> SELECT LEFT(UUID(), 8);
+-----------------+
| LEFT(UUID(), 8) |
+-----------------+
| c26117af |
+-----------------+
1 row in set (0.00 sec)
Random capital letter in MySQL:
mysql> select CHAR( FLOOR(65 + (RAND() * 25)));
+----------------------------------+
| CHAR( FLOOR(65 + (RAND() * 25))) |
+----------------------------------+
| B |
+----------------------------------+
1 row in set (0.00 sec)
Load a random row into a table:
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)
Load random rows:
Make a procedure called dennis that loads 1000 random rows into penguin.
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 |
...
+------+----------+
Update all rows in a table to have random data:
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)

Answer 4

Here is an online tool to generate random data with many options. http://www.generatedata.com/
Just enter the parameters to define what kind of random data you want, and export it to the appropriate format, then you can load it.