Question: There are two tables in two different databases on different servers, I need to join them so as to make few queries. What options do I have? What should I do?

Answer: 
If the database link option is not available, another route you could take is to link the tables via ODBC to something such as MS Access or Crystal reports and do the join there.
While I was having trouble join those two tables, I got away with doing exactly what I wanted by opening both remote databases at the same time. MySQL 5.6 (php 7.1) and the other MySQL 5.1 (php 5.6)

```
//Open a new connection to the MySQL server
$mysqli1 = new mysqli('server1','user1','password1','database1');
$mysqli2 = new mysqli('server2','user2','password2','database2');

//Output any connection error
if ($mysqli1->connect_error) {
    die('Error : ('. $mysqli1->connect_errno .') '. $mysqli1->connect_error);
} else { 
echo "DB1 open OK<br>";
}
if ($mysqli2->connect_error) {
    die('Error : ('. $mysqli2->connect_errno .') '. $mysqli2->connect_error);
} else { 
echo "DB2 open OK<br><br>";
}

```

If you get those two OKs on screen, then both databases are open and ready. Then you can proceed to do your querys.

```
$results = $mysqli1->query("SELECT * FROM video where video_id_old is NULL");
    while($row = $results->fetch_array()) {
        $theID = $row[0];
        echo "Original ID : ".$theID." <br>";
        $doInsert = $mysqli2->query("INSERT INTO video (...) VALUES (...)");
        $doGetVideoID = $mysqli2->query("SELECT video_id, time_stamp from video where user_id = '".$row[13]."' and time_stamp = ".$row[28]." ");
            while($row = $doGetVideoID->fetch_assoc()) {
                echo "New video_id : ".$row["video_id"]." user_id : ".$row["user_id"]." time_stamp : ".$row["time_stamp"]."<br>";
                $sql = "UPDATE video SET video_id_old = video_id, video_id = ".$row["video_id"]." where user_id = '".$row["user_id"]."' and video_id = ".$theID.";";
                $sql .= "UPDATE video_audio SET video_id = ".$row["video_id"]." where video_id = ".$theID.";";
                // Execute multi query if you want
                if (mysqli_multi_query($mysqli1, $sql)) {
                    // Query successful do whatever...
                }
            }
    }
// close connection 
$mysqli1->close();
$mysqli2->close();

```

I was trying to do some joins but since I got those two DBs open, then I can go back and forth doing querys by just changing the connection `$mysqli1` or `$mysqli2` 

It worked for me, I hope it helps... Cheers