Question: I have two tables: users and threads. When a thread is created, it will store the user\_id in the table as author\_id. I want to display the thread name and the username of its author with the same query. I am currently using two querys as shown:

```
$query2 = mysql_query("SELECT author_id FROM threads WHERE id = $threadId") or die(mysql_error());
$result2 = mysql_fetch_array($query2);
$author_id = $result2['author_id'];
$query3 = mysql_query("SELECT username FROM users WHERE id = $author_id") or die(mysql_error());
$result3 = mysql_fetch_array($query3);
$author_name = $result3['username'];

```

Answer: 
```
<?php
$sql = '
    SELECT t.name, u.username
    FROM threads t
    JOIN users u ON t.author_id = u.id
    WHERE t.id = ' . (int)$threadId . '
';
list($thread_name, $author_name) = mysql_fetch_row(mysql_query($sql));

```

P.S. [Mysql php extension](http://php.net/manual/en/book.mysql.php) is deprecated.
Try this query:

```
SELECT username 
FROM users 
WHERE id = (SELECT author_id 
            FROM threads 
            WHERE id = $threadId 
            LIMIT 1)

```

Note: `Limit 1` is not mandatory as id is unique.