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POListing Categories then subcategories in PHP from MySQL database
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  1. POListing Categories then subcategories in PHP from MySQL database
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    copied!<p>I've been working on a project to build a simple ecommerce system that's been going fine until I started working on displaying the navigation for categories.</p> <p>When I build the categories in MySQL I have something like:</p> <pre><code>id name parent_id 1 books null 2 art 1 3 biography 1 4 games null 5 electronics null 6 FPS 4 </code></pre> <p>I've written the following SQL to retrieve the parent categories then the child categories:</p> <pre><code>SELECT parent.name AS parent_name, child1.name AS child1_name FROM categories AS parent LEFT OUTER JOIN categories AS child1 ON child1.parent_id = parent.id WHERE parent.parent_id IS NULL ORDER BY parent_name, child1_name </code></pre> <p>The result of this is an array containing multiple arrays :</p> <pre><code>Array ( [0] =&gt; Array ( [parent_name] =&gt; Books [child1_name] =&gt; Art ) [1] =&gt; Array ( [parent_name] =&gt; Books [child1_name] =&gt; Biography ) [2] =&gt; Array ( [parent_name] =&gt; Clothes, Shoes &amp;amp; Watches [child1_name] =&gt; ) [3] =&gt; Array ( [parent_name] =&gt; Computers &amp;amp; Office [child1_name] =&gt; ) [4] =&gt; Array ( [parent_name] =&gt; Electronics [child1_name] =&gt; ) ) </code></pre> <p>I'm having trouble displaying this information as an unordered list. The desired effect would be something like this:</p> <pre><code>&lt;ul&gt; &lt;li&gt;Books &lt;ul&gt; &lt;li&gt;Art&lt;/li&gt; &lt;li&gt;Biography&lt;/li&gt; &lt;/ul&gt; &lt;/li&gt; &lt;li&gt;Computers&lt;/li&gt; &lt;li&gt;Electronics&lt;/li&gt; &lt;/ul&gt; </code></pre> <p>Does anybody have a solution for this problem? Do I need to change my MySQL code or even the database structure?</p> <p>Thanks in advance.</p>
 

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