Here is a quick and simple way to generate a password your application using MySQL.
This query will create a upper and lower case randomly generated password in length and values.


SELECT CONCAT(UCASE(SUBSTRING(  SUBSTRING(MD5(RAND()), FLOOR( 1 + (RAND() * 5)) , FLOOR( 8 + (RAND() * 15 )) )   , FLOOR( 1 + (RAND() * 4 )) , FLOOR( 4 + (RAND() * 12 )) )),
SUBSTRING('!@#$%^&*', FLOOR( 1 + (RAND() * 4))  , FLOOR( 1 + (RAND() * 8))  ),
SUBSTRING(  SUBSTRING(MD5(RAND()), FLOOR( 1 + (RAND() * 5)) , FLOOR( 8 + (RAND() * 15 )) ) , 5)) as password \G


This query will take a random value for the 1st part of the dynamic password and upper case it when applicable then the second half it adds some symbols then the remaining is in lower case because MD5 does that automatically. You of course can adjust whatever symbols you would prefer.

…

This is not a new feature by any means but it is a question I have happen to see pop up every now and then. So a quick example is following.

To generate a random integer within MySQL you can use the Floor and Rand functions. The MySQL manual documents this here: http://dev.mysql.com/doc/refman/5.5/en/mathematical-functions.html#function_rand

"To obtain a random integer R in the range i <= R < j, use the expression FLOOR(i + RAND() * (j – i))"

So to give an example:

> SET @I = 3; # lower range
> SET @J = 43 - @I; # max range minus lower range

> SELECT FLOOR( @I + (RAND() * @J )) as lottery_numbers\G
…