Range of IDs that are then set to Random?

[PHPAnx]

Alrighty, I've rewritten this query about 500 times. I'm getting nowhere. Here's the mysql query:

$result=mysql_query("SELECT *, MD5( RAND( NOW( ) ) ) AS myRandom FROM records WHERE recordsID BETWEEN '900' AND '920' ORDER BY myRandom LIMIT 0,4") or die ("No results found.");

Let me explain what I am trying to do:

I want to take the last 20 records in my database and then only display 4 of them at a time, but display them randomly.

I am only able to accomplish this with the above query if I hardcode the last row's ID (920)and the ID of the row 20 before it (900).

Is there a way I can replace the "920" with a the last row ID dynamically and then calculate like last row id - 20 to get the other number? Am I making sense?

Thanks

[bradgrafelman]

Try this:

SELECT * FROM (
    SELECT col1, col2
    FROM records
    ORDER BY recordsID DESC
    LIMIT 20
) AS results
ORDER BY RAND()

Now, what do you mean "4 at a time" ? Are you talking about grouping them visually?