display other text if there is no sql data to display

sorry if i'm describing something wrong or ambiguously, i'm somewhat of a noob at php and mysql, i'm just trying to write a basic comment system for a website.

if there is no mysql data to display (due to filters or empty rows), how would you display alternate text ("No comments")?

thanks

 

$getAll = mysql_query("SELECT * FROM `XXXXX`",$SERVER);
if (mysql_num_rows($getAll) == 0) {
echo '<tr><td colspan="3" align="center">Nothing found.</td></tr>';
}
else {
while($data = mysql_fetch_array($getAll)) {
echo
}