Re: check unread messages in a forum

>I have made a forum in PHP, and the users are logged in using cookies. I >want all new threads (and if there are new replies in an old thread) to be >highlight or something like that. > >How do I check if a user has read a message or not? Every user has a unique ID when they log in, right? And every message has a unique ID, right? create table messages_read( user_id int(11) unsigned not null key, message_id int(11) unsigned not null key ); When they read a message: $query = "insert into messages_read(user_id, message_id) values($user_id, $messages_id)"; You can then use this in the query that gets the messages for display: select blah, blah blah, messages_read.user_id from messages left outer join messages_read on user_id = $user_id and messages_read.message_id = messages.message_id where blah, blah, blah The "left outer join ..." part is the new bit in your query. Notice also that I've added "messages_read.user_id" to the columns you select. As you iterate through the messages to display, either: 1. messages_read.user_id is their $user_id, and they've read that message or, 2. messages_read.user_id is NULL because there was no row in the messages_read table, so they ain't seen that message yet. Be sure to add interface elements so that they can mark a message "Read" or "Unread" even if they've already read it or haven't -- Let the user have control over what they consider as "Read" or they'll be only partially happy about this new feature. :-) -- Like Music? http://l-i-e.com/artists.htm