This is probably what you are looking for:
SELECT m.subject,m.status,u.user_id FROM messages m LEFT JOIN user u ON m.sender_user_id=u.user_id WHERE u.user_id IS NULL
That will give you all message without a related user.
On Dec 8, 2004, at 6:30 AM, Merlin wrote:
Hi there,
I know this is a question for the mysql mailing list, but maybe one of you guys also could help out with that.
I do have to tables (users, messages). Now there unfortunatelly are some messages where the sender in the user table is missing.
I am trying to find all messages which do not have the belonging user anymore.
So I tried this: SELECT m.subject, m.status FROM user u, messages m WHERE m.sender_user_id != u.user_id
But this returns far to many rows.
Has anybody an idea how to do that?
Thank you in advance,
Merlin
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