关于联接的PHP MySQL查询

Question

I have a newbies PHP MySQL question, I have 2 tables, members and messages.

Table 'members'

+-----------+------+
| MEMBER_ID | NAME |
+-----------+------+
|         1 | Bob  |
|         2 | Ted  |
|         3 | Tom  |
+-----------+------+

Table 'messages'

+----+------------+--------------+--------------------+
| ID | SENDERS_ID | RECEIVERS_ID |      MESSAGE       |
+----+------------+--------------+--------------------+
|  1 |          1 |            3 | Hello Tom from Bob |
|  2 |          2 |            3 | Hello Tom from Ted |
|  3 |          2 |            1 | Hello Bob from Ted |
+----+------------+--------------+--------------------+

I want to make a query where Tom only having his members.member_id available can get all of his messages along with name of the sender like this:

+------+--------------------+
| name |      message       |
+------+--------------------+
| Bob  | Hello Tom from Bob |
| Ted  | Hello Tom from Ted |
+------+--------------------+

I have read some examples of joins but do know how to implement them into a MySQL statement.

I can get Tom's member_id easily but do not know how to proceed further. I also want to return the result in an array.

  public function getMessages($member_id) {

  $result = mysql_query("SELECT member_id FROM members WHERE member_id = '$member_id'") or die(mysql_error());
    $no_of_rows = mysql_num_rows($result);
    if ($no_of_rows > 0) {
        $result = mysql_fetch_array($result); 
        $receivers_id = $result['member_id'];
        .
        // What can I do here to get the $result that I want?
        .
    }
    $no_of_rows = mysql_num_rows($result);
    if ($no_of_rows > 0) {
        $results = array();
        while(list($results) = mysql_fetch_array($result)) {
            array_push($results, $result);
        } 
        return $results;
    }
}       

Any help would be greatly appreciated,

Thanks

Answer 1

SELECT  c.name,
        b.message
FROM    members a
        INNER JOIN  messages b
            ON a.member_ID = b.receivers_id
        INNER JOIN members c
            ON b.senders_ID = c.member_ID
WHERE   a.name = 'Tom'

• SQLFiddle Demo