Get list of messages from one table, message list indicator from

another. What's wrong with this query?

[HughMungus]

I have two tables. One has a list of messages left by users using fields named mbxno for the mailbox and msgno for the message number. I have another table that has mailbox settings for each user that contains a field named "messagelist" to indicate if they want to be included on the message list or not.

What I'm trying to create is a list of the most-recent messages with a lookup on the users table to indicate whether a message in the list should be included in the message list based on the user's mailbox settings.

SELECT messages.msgno, messages.mbxno, users.messagelist FROM messages, users WHERE (users.messagelist = '1') ORDER BY msgno DESC LIMIT 100

What I'm getting, though is a list that looks like this:

mbxno: 1114 msgno: 0412141623 msglist: 1
mbxno: 1114 msgno: 0412141623 msglist: 1
mbxno: 1114 msgno: 0412141623 msglist: 1
mbxno: 1114 msgno: 0412141623 msglist: 1
mbxno: 1114 msgno: 0412141623 msglist: 1
mbxno: 1114 msgno: 0412141623 msglist: 1
mbxno: 1114 msgno: 0412141623 msglist: 1
mbxno: 1114 msgno: 0412141623 msglist: 1

I think what's happening is that I'm using the wrong type of join and more rows are being created than necessary.

If I add "DISTINCT" to the query, I get a list of the most-recent messages as I expect, but the "messsagelist" value is sometimes wrong (again, probably because the data is getting jumbled). For example, the messagelist value for the second row (2214) should be 0, not 1.

mbxno: 1114 msgno: 0412141623 msglist: 1
mbxno: 2214 msgno: 0412141622 msglist: 1
mbxno: 2189 msgno: 0412141408 msglist: 1
mbxno: 0000 msgno: 0412141213 msglist: 1
mbxno: 0003 msgno: 0412141213 msglist: 1
mbxno: 2265 msgno: 0412132029 msglist: 1
mbxno: 0000 msgno: 0412131950 msglist: 1

How should I be doing this? If nothing else, what kind of join will work with a long list compared to a value from a short list?

[Salsa]

Assuming you have a column like 'user' in each table, as it seems you would, would it help to make your WHERE clause something like

WHERE users.messagelist = '1' AND messages.user = users.user

...otherwise, you're going to match up every record from messages with each record from users.

I hope this helps

[HughMungus]

I was making it too complicated, I see.

Thanks so much salsa.