title: MySQL query to get a list of user from conversation list
body: <p>I have a mysql table chat like</p>
  
  <pre><code>+---------+-----------+-------------+----------------+
  | chat_id | sender_id | receiver_id | msg            |
  +---------+-----------+-------------+----------------+
  |       1 |      1002 |        1001 | test           |
  |       2 |      1001 |        1002 | test           |
  |       3 |      1002 |        1001 | test           |
  |       5 |      1001 |        1002 | asdf           |
  |       6 |      1003 |        1001 | tesdf          |
  |       9 |      1001 |        1003 | tasdfa a fasd  |
  |      10 |      1001 |        1004 | dsf asdf a     |
  |      11 |      1005 |        1001 | dsf asdf asdf  |
  +---------+-----------+-------------+----------------+
  </code></pre>
  
  <p>There is conversation of user 1001 among users 1002,1003,1004,1005</p>
  
  <p>I need a list of users(1002,1003,1004,1005) whom with user 1001 did conversation.</p>
  
  <p>What will be the mysql query? please help me.</p>