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    <p>Well, there are a few patterns you could use. Which one is right depends on your needs. </p> <p>Do you need to select a node and all its children? If so, then a <a href="http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/" rel="nofollow noreferrer">Nested set Model (Scroll down to the heading)</a> may be better for you. The table would look like this:</p> <pre><code>| Name | Left | Right | | Emails | 1 | 12 | | Business | 2 | 7 | | Tim's | 3 | 4 | | 7-11 | 5 | 6 | | Churches | 8 | 11 | | St. Pete | 9 | 10 | </code></pre> <p>So then, to find anything below a node, just do</p> <pre><code>SELECT name FROM nodes WHERE Left &gt; *yourleftnode* AND Right &lt; *yourrightnode* </code></pre> <p>To find everything above the node:</p> <pre><code>SELECT name FROM nodes WHERE Left &lt; *yourleftnode* AND Right &gt; *yourrightnode* </code></pre> <p>If you only want to query for a specific level, you could do an <a href="http://mikehillyer.com/articles/managing-hierarchical-data-in-mysql/" rel="nofollow noreferrer">Adjacency List Model (Scoll down to the heading)</a>:</p> <pre><code>| Id | Name | Parent_Id | | 1 | Email | null | | 2 | Business | 1 | | 3 | Tim's | 2 | </code></pre> <p>To find everything on the same level, just do:</p> <pre><code>SELECT name FROM nodes WHERE parent_id = *yourparentnode* </code></pre> <p>Of course, there's nothing stopping you from doing a hybrid approach which will let you query however you'd like for the query at hand</p> <pre><code>| Id | Name | Parent_Id | Left | Right | Path | | 1 | Email | null | 1 | 6 | / | | 2 | Business | 1 | 2 | 5 | /Email/ | | 3 | Tim's | 2 | 3 | 4 | /Email/Business/ | </code></pre> <p>Really, it's just a matter of your needs...</p>
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    1. POWhat type of data structure should I use for mimicking a file-system?
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    1. COYep! Nested Set Model is exactly what I was looking for! Thank youuuuuuuuuu!
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