สร้าง array จาก mysql คะ จะนำค่า ID_member Where active =1 ซึ่งก็คือ [4 7 10 11 13 15] มาสร้างเป็น array ยังไงคะ

$querystring = "select id_member from table where active = 1";
$sql = mysql_query($querystring);
$fet = mysql_fetch_array($sql);

print_r($fet);

include("connect.php");
$sql="select * from user WHERE active = 1";
$res=mysql_query($sql);
while($row=mysql_fetch_array($res)){
     echo $row["id_member"];
}

<?PHP
include("connect.php");
$sql="select * from user WHERE active = 1";
$res=mysql_query($sql);
while($row=mysql_fetch_array($res)){
     $arr[] = $row['ID_member'];
}
print_r($arr);
?>

<?PHP
include("connect.php");
$sql="select * from user WHERE active = 1";
$res=mysql_query($sql);
$row=mysql_fetch_array($res);

print_r($row);
?>

<?PHP
include("connect.php");
$sql="select * from user WHERE active = 1";
$res=mysql_query($sql);
$arr=array();

while($row=mysql_fetch_array($res)){
     array_push($arr,$row['ID_member']);
}
print_r($arr);
?>