Invalid argument i mysql_fetch_assoc()

Jeg modtager denne fejlmeddelelse:
Warning: mysql_fetch_assoc(): supplied argument is not a valid MySQL result resource

Hvorfor?

mysql_connect('*****', '********', '*******');
mysql_select_db('*********');
$query = mysql_query("SELECT nyhedsID,overskrift,indhold,DATE_FORMAT(date,'%e/%c-%y') AS date FROM nyhed WHERE parent=0 ORDER BY nyhedsID DESC LIMIT 1");
$row = mysql_fetch_assoc($query);
if($row == 0) {
    echo "Keine nyheder";
} else {
    while($row = mysql_fetch_assoc($query)) {

echo "<h1>" .$row['overskrift']. "</h1>";
echo "<p>";
echo nl2br($row[indhold]);
echo "<br /><br /><span style=\"color:#666666;\">Skrevet:&nbsp;";
echo $row['date'];
echo "</p>";
}
}