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    <p>This was hand-written in a text editor... I don't have a dev environment handy so appologies if this is just plain wrong or contains typos.</p> <p>But regardless I think the idea is clear/sound.</p> <p>The <code>$sql</code> would be:</p> <pre><code>SELECT parent.id as parentid, parent.[name] as parentname, child.[name] as childname FROM category child left join category parent -- Can't exclude parents with no children, else they won't appear in the list! on child.parent = parent.id ORDER BY parentid </code></pre> <p>And then the PHP would be:</p> <pre><code>function categoryLevels(){ $bullet = "*"; // You can specify your HTML/CSS :-) $indent = " "; // You can specify your HTML/CSS :-) $sql = "_as above_"; $query = mysql_query($sql); $lastParentId = 0; while($row = mysql_fetch_array($query)){ $parentId = $row['parentid'] if ($parentId != 0) { if ($parentId != $lastParentId) { echo $bullet . $row['parentname'] $lastParentId = $parentId; } if (!is_null($row['childname']) { // this line is psuedo-code! - don't know the php equiv for is_null, sorry. echo $indent . $bullet . $row['childname']; } } } } </code></pre> <p>The gist of this is basically:</p> <ol> <li>Get a result set of all categories (excluding those with no parents), sorted by the parent to which they belong </li> <li>Iterate that result set, and for each change in parent, output a "header" with the parent name.</li> <li>Output the child.</li> </ol> <p>Edited this to be less complex (and faster). Now the SQL simply excludes the parent rows altogether, rather than excluding them with the <code>IF</code> statement in the PHP.</p>
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    1. POGet categories in hierarchical format from database
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    1. POGet categories in hierarchical format from database
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    1. COUnbelivably it works. With html code combined its working as I needed. Thanks @Sepster. +1 for you.
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    2. CO@user1995997 Nice! I've just realised though, with my recent edit (replaced `left` join with `inner`, and removed `if`), you'll lose categories that have no children. So please revert to `left` join, and re-instate the `if` block. Will update my answer.
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    3. CO@user1995997 And also realised that it now needs a check for null child... so that it doesn't echo an empty bullet. Code updated (with some psuedo-code) to reflect this. Thanks heaps for the votes/accept, I really appreciate it. And re your thanks: My pleasure, glad I could help.
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