Database connections

Typically, Laravel uses a "global" database connection and assumes you are handling access control and permissions at the application level. It's possible to use different connections, but I don't think it will be very manageable to manage roles this way in Laravel.

Instead, I would look at implementing access control or roles within the Laravel application. This package from Spatie looks like a good starting point.

Create a new database config in /config/databases.php to use as the 2nd connection. You can leave some values blank, like username, password, database, etc.

'yourCustomConfig' => [
    'host' => '196.168.1.2'
    'driver'    => 'mysql',
    'database'  => '',
    'username'  => '',
    'password'  => '',
    'charset' => 'utf8mb4',
    'collation' => 'utf8mb4_unicode_ci',
    'prefix'    => '',
],

Then before you want to access it, you can change the values dynamically

Config::set("database.connections.yourCustomConfig", [
    "host" => "1.2.3.4",
    "database" => "differentDBName",
    "username" => "Billy",
    "password" => "Bob"
]);

Now any model using the 'yourCustomConfig' connection will use those values to connect for the duration of that request. You'd have to set it each time in between requests.

SomeModel::on('yourCustomConfig')->find(123);

or

DB::connection('yourCustomConfig')->table('someTable')->where('something', 'other')->get();

Set up another set of env variables, add another connection similar to the MySQL array but obviously name something else. In your user model you can set the connection to your oracle db:

protected $connection = 'name'

A caviate is you have to authorize users your self as the hash won't work (auth()->attempt()). But once you authorize the user you can manually log them in. auth()->login(userObject).

Unfortunately I'm in a similar boat using active directory (ms sql) for users and acl. Not a huge deal but a little extra work.