I apologize for the late reply, I was transferred to a new project and forgot about it. I ended up using a standard PHP PDO connection.
Here is an example:
// connection variables
$servername = "localhost";
$database = "database";
$user = "username";
$pass = "password";
try {
//create connection
$DBH = new PDO('sqlsrv:Server=".$servername.";Database=".$database, $user, $pass);
$DBH->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );
//insert project
$insert_data = array(
"id' => $client_id,
'name' => $client_name
);
$STH = $DBH->prepare("INSERT INTO dbo.clients (id, name) VALUES (:id, :name); ");
$STH->execute($insert_data);
// close the connection
$DBH = null;
}
catch(PDOException $e)
{
echo $e->getMessage();
}
For more information please see these links, or google PHP PDO.
https://stackoverflow.com/questions/2328224/how-do-i-retrieve-external-data-from-ms-sql-from-a-wordpress-blog (as suggested by Pat J)
http://net.tutsplus.com/tutorials/php/why-you-should-be-using-phps-pdo-for-database-access/