$hostname = "servername";
$username = "username";
$password = "password";
$dbName = "dbname";

MSSQL_CONNECT($hostname,$username,$password) or DIE("DATABASE FAILED TO RESPOND.");
mssql_select_db($dbName) or DIE("Database unavailable");

$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// Create connection
$conn = mysqli_connect($servername, $username, $password, $dbname);
// Check connection
if (!$conn) {
    die("Connection failed: " . mysqli_connect_error());
}

$hostname = "servername";
$username = "username";
$password = "password";
$dbName = "dbname";

$conn = MYSQL_CONNECT($hostname,$username,$password) or DIE("DATABASE FAILED TO RESPOND.");
mysql_select_db($dbName) or DIE("Database unavailable");

$query = "select * from table";
$rs = mysql_query($query, $conn);
$rw = mysql_fetch_array($rs);
foreach($rw as $value){
echo $rw['col_name'];
}

$servername="(server name)"; // use local if local server
$conn=new PDO("sqlsrv:server=$servername; database=dbname");
if($conn){

    //echo "success";
}
else{
    echo "error";
    die(print_r(sqlsrv_errors(),true));
}