getDoctor.php

<?php
include 'libs/db.class.php';
$db = NEW DB();
$sql = "SELECT users.id, (employee.name || ' ' || employee.lastname) AS name FROM users LEFT JOIN employee ON employee.id=users.employee WHERE role=6 AND employee.name IS NOT NULL";
$data = $db->doSql($sql);
do {
    $doctors[] = array(
        'id' => $data['id'], 
        'name' => $data['name']
    );
} while ($data = pg_fetch_assoc($db->actualResults));
echo json_encode($doctors);
?>