Fehler bei MYSQL ausfrage

Hallo. Ich kenne mich noch nicht so gut mit MYSQL aus, immer wenn ich auf meine seite gehe steht dort immer:

Warning: mysql_fetch_assoc() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs\data_classes\server-data.php_data_classes-core.php.php on line 54

Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs\data_classes\server-data.php_data_classes-core.php.php on line 275

Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in C:\xampp\htdocs\data_classes\server-data.php_data_classes-core.php.php on line 301

Warning: Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\data_classes\server-data.php_data_classes-core.php.php:54) in C:\xampp\htdocs\data_classes\server-data.php_data_classes-core.php.php on line 339

für zeile 54:

$cms_settings = mysql_query("SELECT * FROM cms_settings LIMIT 1");
$config = mysql_fetch_assoc($cms_settings);


$maintenance = mysql_num_rows($maintenance = mysql_query("SELECT * FROM cms_settings WHERE variable = 'cms_maintenance' AND value = '1'"));


$server = mysql_fetch_assoc($server_status = mysql_query("SELECT * FROM server_status"));
$online_count = $server['users_online'];

für zeile 275:

$hc_a = mysql_query("SELECT * FROM user_subscriptions WHERE user_id = '".$my_id."' and timestamp_expire > '".time()."'");
	$hc = mysql_num_rows($hc_a);


	function getHCDays($my_id){


		$sql = mysql_query("SELECT timestamp_activated,timestamp_expire FROM user_subscriptions WHERE user_id = '".$my_id."' LIMIT 1") or die(mysql_error());

		if (mysql_num_rows($sql) == 0){
			return 0;

für zeile 301:

$vip_a = mysql_query("SELECT * FROM vip WHERE id_user = '".$my_id."'");
	$vip = mysql_num_rows($vip_a);


	function getVIPDays($my_id){


		$sql = mysql_query("SELECT timestamp,timestampend FROM vip WHERE id_user = '".$my_id."' LIMIT 1") or die(mysql_error());

		if (mysql_num_rows($sql) == 0){
			return 0;

für zeile 339:

if($maintenance == '1' && !$is_maintenance && $rank['iAdmin'] < 1){
	header("Location: ".$path."/maintenance");
	exit;
} elseif($rank['iAdmin'] == 1 && $config['variable'] == "cms_maintenance" && $config['value'] == '1'){
	$notify_maintenance = true;

Danke schonmal falls mir jemand weiter helfen kann