<?php
$serverName = "serverName\sqlexpress";
$connectionInfo = array( "Database"=>"dbName", "UID"=>"username", "PWD"=>"password");
$conn = sqlsrv_connect( $serverName, $connectionInfo);
if( $conn === false) {
    die( print_r( sqlsrv_errors(), true));
}

$sql = "UPDATE Table_1
        SET OrderQty = ?
        WHERE SalesOrderID = ?";

// Initialize parameters and prepare the statement. 
// Variables $qty and $id are bound to the statement, $stmt.
$qty = 0; $id = 0;
$stmt = sqlsrv_prepare( $conn, $sql, array( &$qty, &$id));
if( !$stmt ) {
    die( print_r( sqlsrv_errors(), true));
}

// Set up the SalesOrderDetailID and OrderQty information. 
// This array maps the order ID to order quantity in key=>value pairs.
$orders = array( 1=>10, 2=>20, 3=>30);

// Execute the statement for each order.
foreach( $orders as $id => $qty) {
    // Because $id and $qty are bound to $stmt1, their updated
    // values are used with each execution of the statement. 
    if( sqlsrv_execute( $stmt ) === false ) {
          die( print_r( sqlsrv_errors(), true));
    }
}
?>

Code

Result

PHP code example: sqlsrv_prepare

Prepares a query for execution. See documentation.

You can try this function yourself. Just edit the code and on "Run" to see the result.