Which structure in MySQL db for a cat sub sub situation

For one of my new projects I have to create a category page with head category, sub category and sub sub categorie. for example;

• Internet
• Internet > Developing
• internet > Developing > Mobile apps

In this categories you can find websites about these things. I have to give every website the id of the category? what do I have to do if I want to show all these websites开发者_开发技巧 related to 'Internet > developing' at 'Internet' (the head category?)

Thanks in advice.

Regards, Nicky

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This is typical situation where the Nested Sets model is very useful

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In dev.mysql there was a guide to work with hierachical daat :(

I haven't try this but I just got it http://explainextended.com/2009/03/17/hierarchical-queries-in-mysql/

Also, if you look for "hierachical data" mysql, you will get a lot of options to do what you need.