Messaging System with PHP/MySQL

Question

Hi I\'m trying to make a messaging system with php and mysql.

The mysql table is simple: id sender receiver text timestamp

I\'m trying to make the messaging some

Answer 1

UPDAte: I'm not sure if it works perfect:

SELECT * FROM messages 
WHERE receiver = 13
GROUP BY receiver,sender 
ORDER BY timestamp DESC
LIMIT 1

UNION ALL
SELECT * FROM messages 
WHERE sender = 13
GROUP BY receiver,sender 
ORDER BY timestamp DESC
LIMIT 1

to reverse the order:

ORDER BY timestamp DESC