Building on other answers, here's how to do the loop and hit the database only once.

$query = "INSERT INTO downloads (downloadkey, file, expires) VALUES ";









while ($row = mysql_fetch_array($resultstwo)) {




    $strKey = createKey();




    $time = time()+(60*60);









    $query .= "('{$strKey}', '{$row['filename']}', {$time}),";




    echo "<a href='download.php?key=$strKey'>{$row['caption']}</a>";




}









$query = substr ( $query, 0, -1 ); // Remove the last comma.









mysql_query ( resDB, $query );

The end result of the query will be something like:

INSERT INTO downloads (downloadkey, file, expires) VALUES 




                      ('adfsdfgsdgs', 'Bladerunner.avi', 12345678),




                      ('dfghfyadfsg', 'How_I_met_your_mother.avi', 12345678),




                      ('34t34t3t', 'Simpson_the_movie.avi', 12345678),




                      ('taert43te', '{$row['filename']}', 12345678),




                      ('at43t3t', '{$row['filename']}', 12345678),

This will insert all the values into mysql using this one query only.