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POTrying to simplify a MySQL query
 

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  1. POTrying to simplify a MySQL query
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    <p>I would really appreciate any help trying to simplify a MySQL query. The purpose of the query is to retrieve messages from a messages table (users_messages) which has the following columns: message_id, from_id, to_id, message_content, date_sent.</p> <p>The from_id and to_id need to join a users table (users) which has these columns: user_id, user_username.</p> <p>Also I should mention that there is a blocked users table (users_blocked) which filters out any messages should the user_id feature in this table.</p> <p>All this works fine and messages are ordered with the newest first which is what I want. My only problem is that it's not pulling the corresponding 'message_content'. i.e. it's pulling the most recent date, but not the most recent message.</p> <p>Perhaps I need a different approach (e.g. subqueries) but I can not get my head around it.</p> <p>Here is the query:</p> <pre><code>select m.message_content, if(from_id &lt; to_id, concat(from_id,to_id), concat(to_id,from_id)) as ft, if (from_id = $my_id, to_id, from_id) as other_id, max(date_sent) as most_recent from users_messages m left join users_blocked ub1 on (from_id = ub1.blocked_id and ub1.user_id = $my_id) left join users_blocked ub2 on (to_id = ub2.blocked_id and ub2.user_id = $my_id) where (from_id = $my_id or to_id = $my_id) and ub1.blocked_id is null and ub2.blocked_id is null group by ft order by most_recent desc </code></pre> <p>Sorry, here are the table structures:</p> <p>users</p> <pre>user_id user_username 1 Simon 2 Amber 3 Tom</pre> <p>users_messages</p> <pre> message_id from_id to_id date_sent message_content 1 1 2 2012-07-04 11:52:12 Hello 2 1 2 2012-07-04 12:32:24 Another message 3 1 2 2012-07-04 14:00:00 Hello again </pre> <p>users_blocked</p> <pre> user_id blocked_id 1 3 </pre>
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    1. USSimon King
    1. USSimon King
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    1. COPlease include your table structure(s). Also - it's returning `message_content` but it isn't the correct value? Or it's not returning anything?
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      1. POTrying to simplify a MySQL query
      1. USethrbunny
    2. COThat's not too bad. Hell, you can read it all without scrolling, which is always a bonus!
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      1. USGrim...
    3. COnot terrible but I would probably just get an array of blocked users and do a not in for the from_id
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      1. UStimpone
 

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