Question

Using PHP and MySQL, I’m trying to get all the private chats involving the actual user.
For that I have a table called “rooms” (id, id_initiate_user, id_target_user) and another one called “users” (id_pseudo, avatar).
If the actual user is the initiating user of a chat room, I want to get the avatar and pseudo from the target user and if the actual user is the target user of the that room, I want to get the avatar and pseudo from the initiating user (whatever the case, I want the other member’s avatar and pseudo).

I guess I need a condition in my query then but I really don’t know how to manage it (googled all day long).

Here is my query (the logic is there but the syntax is obviously wrong:

$user_id=$_SESSION['user_id'];

$res = @mysql_query("
SELECT rooms.id, rooms.id_initiate_user, rooms.id_target_user, rooms.pv, users.id, users.pseudo, users.avatar 
FROM rooms, users 
WHERE 
(
    (rooms.id_initiate_user='$user_id' OR rooms.id_target_user='$user_id') 
    AND  
    (
        IF (rooms.id_initiate_user='$user_id')
        THEN rooms.id_target_user=users.id
        ELSE rooms.id_initiate_user=users.id;
        END IF;
    )
) ORDER BY rooms.id ASC");

I read plenty of questions around here regarding the “conditional where” but none of it solved my case.
Thank you for your help.

Answer 1

Can’t you do something like this:

WHERE 
(
    (
        rooms.id_initiate_user='$user_id'
        AND rooms.id_target_user=users.id
    )
    OR
    (
        rooms.id_target_user='$user_id'
        AND rooms.id_initiate_user=users.id
    )
)