error code warning mysql_fetch_array(): supplied argument is not a valid MySQL result resource

$rsExtValue = mysql_fetch_array(mysql_query("select ext_id from proext_auc where pid='$pid'"));
	$ext_no = $rsExtValue['ext_id'];
	
	if($ext_no == 1 || $ext_no == 2) {
		$getqry = get_extpro($pid,$ext_no);
	}
	while($row=mysql_fetch_array($getqry))
	{
		$ext_id = $row[0];
		if($ext_id==$ext_no)
		{
			return true; 
		}
	}
		return false;
}