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troubleshooting Question

MySQL: How can I return true if a field matches an entry in another table?

Avatar of davideo7
davideo7Flag for United States of America asked on
7 Comments1 Solution413 ViewsLast Modified:
This is going to be hard to explain but I have a while loops which loops through results.  The results are of threads that I have on my forum as seen here:

What I want to do is while retrieving the threads from the DB, I want the query to also compare each thread with another table called 'auto_mark_forums_read' which basically checks to see if a user has read that thread and if they haven't, display a New icon.

Below in my code you'll see the query I have which retrieves all of the threads from the DB.
SELECT t.*,u1.name AS name1,u1.sex AS sex1,u1.powerlevel AS power1,u2.name AS name2,u2.sex AS sex2,u2.powerlevel AS power2 FROM threads t,users u1,users u2 WHERE forum=$id AND u1.id=t.user AND u2.id=t.lastposter $subforumtext ORDER BY sticky DESC,lastpostdate DESC
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