If your specs are that specific (IDs must be between 1 and 999999) then you could create a 999999-row table with one integer column and prefill it with the numbers 1 to 999999 in random order.
Then you could write a function that would select and return the first number in the table, then delete that record so you would not reuse it. Once you've done the work of sorting 999999 numbers in random order (which can be done anywhich way) it's easy and you don't have to loop an indeterminant number of times. You would be looping an increasing number of times as you begin to fill up the table. Jim On Fri, May 28, 2010 at 10:38 AM, Andre Matos <andrema...@mineirinho.org> wrote: > Hi All, > > I have a table that uses auto_increment to generate the Id automatically > working fine. However, I need to create a new table where the Id must be a > number generated randomly, so I cannot use the auto_increment. > > MySQL has a function RAND. So I could use something like this: > > SELECT FLOOR(RAND() * COUNT(*)) AS RandId FROM mytable > > But, let's suppose that the RandId is a number that was already used in the > table. Then I need to run the SELECT again and again until I find a number > that hasn't been used. > > Is there a way to have this SELECT to loop until it finds a number that > hasn't been used? > > The RandId must be only numbers and length of 6 (from 1 to 999999). No other > character is allowed. > > Thanks for any help! > > Andre > > -- > Andre Matos > andrema...@mineirinho.org > > > > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/mysql?unsub=jlyons4...@gmail.com > > -- Jim Lyons Web developer / Database administrator http://www.weblyons.com -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/mysql?unsub=arch...@jab.org
