<?php
$sql = mysql_query('SELECT * FROM `table`');
$row = mysql_fetch_assoc($sql);
$user = $row['user'];
$sql123 = "SELECT * FROM `table` WHERE autor='$user'";
$ress = @mysql_query($sql123) or die(mysql_error());
$num = mysql_num_rows($ress);
echo 'Качени файлове: <b>'.$num.'</b>';
?>