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    <p>Use <code>LEFT JOIN</code> instead of <code>INNER JOIN</code>. The two joins are different from each other. The <code>INNER JOIN</code> (<em>which you are currently using</em>) only returns the records which both has at least one match on either side of the table. And that is why <code>computer 14</code> won't should because it has no match on table <code>COMPUTER_HARDDRIVES</code>. <code>LEFT JOIN</code> on the other hand, returns all records on the <em>left hand side</em> table whether it no match on the other side of the tables.</p> <pre><code>SELECT a.ID AS UserID, a.Name as UserName, b.ID as ComputerID, d.ID as ProcessorID, d.Name as ProcessorName, f.ID as HardDriveID, f.name as HardDriveName FROM users a INNER JOIN computers b ON a.ID = b.user_ID LEFT JOIN computer_processors c ON b.ID = c.C_ID LEFT JOIN PROCESSORS d ON c.p_ID = d.ID LEFT JOIN COMPUTER_HARDDRIVES e ON b.ID = e.c_ID LEFT JOIN HARDDRIVE f ON e.h_ID = f.ID WHERE a.ID = 1 </code></pre> <ul> <li><a href="http://sqlfiddle.com/#!2/f2ab6/1" rel="nofollow"><strong><em>See SQLFiddle Demo</em></strong></a></li> <li>for more details about joins, see <a href="http://www.codeproject.com/Articles/33052/Visual-Representation-of-SQL-Joins" rel="nofollow"><strong>Visual Representation of SQL Joins</strong></a></li> </ul> <p>and since you want to groupt the rows together, youcan take advantage of <code>GROUP_CONCAT()</code> function. basically, what it does is it combines the value of the columns into comma separated value</p> <pre><code>SELECT a.ID AS UserID, a.Name as UserName, b.ID as ComputerID, GROUP_CONCAT(DISTINCT d.ID) as ProcessorID, GROUP_CONCAT(DISTINCT d.Name) as ProcessorName, GROUP_CONCAT(DISTINCT f.ID) as HardDriveID, GROUP_CONCAT(DISTINCT f.name) as HardDriveName FROM users a INNER JOIN computers b ON a.ID = b.user_ID LEFT JOIN computer_processors c ON b.ID = c.C_ID LEFT JOIN PROCESSORS d ON c.p_ID = d.ID LEFT JOIN COMPUTER_HARDDRIVES e ON b.ID = e.c_ID LEFT JOIN HARDDRIVE f ON e.h_ID = f.ID WHERE a.ID = 1 GROUP BY UserID, UserName, ComputerID </code></pre> <ul> <li><a href="http://sqlfiddle.com/#!2/5bca8/1" rel="nofollow"><strong><em>See SQLFiddle Demo</em></strong></a></li> </ul>
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    1. POUser has many computers, computers have many attributes in different tables, best way to JOIN?
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    1. POUser has many computers, computers have many attributes in different tables, best way to JOIN?
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    1. COHi, thanks for your help, both approaches work beautifully! I'm a litte worried about the GROUP_CONCAT(DISTINCT...) though, since it uses a comma to separate the values, and some of the values in my columns can potentially already have a comma (like 'processor type 25, xx'), and then it will be very hard to sort from there. I think I will go with the first approach and then sort everything in application code. Which one of the approaches would you choose?
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    2. COactually you don't have to worry about the separator because you can change it and you can also sort it inside `group_concat`. [*Click here for demo*](http://sqlfiddle.com/#!2/5bca8/2).
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    3. CO[SQL Fiddle Demo (GROUP_CONCAT with ORDER BY and SEPARATOR change)](http://sqlfiddle.com/#!2/5bca8/5)
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