I'm doing a page that works with 2 postgresql database managers and sql server, postgres is on the application server and sql server can be on the same server or on another server my question is how can I connect with the server sql server being on the other side and list the database that has to select which one to connect to, because the databases do not always have the same name, I leave the html code of what else I want to do
<!DOCTYPE html>
<html lang="en">
<head>
<title>Conección</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.0/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.0/umd/popper.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.1.0/js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<h2>Conectar Base de Datos</h2>
<form >
<div class="form-group">
<label for="usuario">Usuario:</label>
<input type="usuario" class="form-control mb-2 mr-sm-2" id="usuario" placeholder="Usuario" name="usuario">
</div>
<div class="form-group">
<label for="pwd" class="mr-sm-2">Contraseña:</label>
<input type="password" class="form-control mb-2 mr-sm-2" id="pwd" placeholder="Contraseña" name="pswd">
<label for="servidor" class="mr-sm-2">Servidor:</label>
<input type="servidor" class="form-control mb-2 mr-sm-2" id="servidor" name="servidor" placeholder="Servidor">
<label for="database" class="mr-sm-2">Base de Datos:</label>
<select>
<option value="">Seleccionar ...</option>
</select>
</div>
<button type="submit" class="btn btn-primary">Conectar</button>
</form>
</div>
</body>
</html>