MySQL: 4 Table "has-many-through" Join?

Posted by Nebs on Stack Overflow See other posts from Stack Overflow or by Nebs
Published on 2010-04-14T19:57:09Z Indexed on 2010/04/14 20:03 UTC
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mysql

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join

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has-many-through

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php

Let's say I have the following 4 tables (for examples' sake): Owners, Trucks, Boxes, Apples.

An owner can have many trucks, a truck can have many boxes and a box can have many apples.

Owners have an id. Trucks have an id and owner_id. Boxes have an id and truck_id. Apples have an id and box_id.

Let's say I want to get all the apples "owned" by an owner with id = 34. So I want to get all the boxes that are in boxes that are in trucks that owner 34 owns.

There is a "hierarchy" if you will of 4 tables that each only has reference to its direct "parent". How can I quickly filter boxes while satisfying conditions across the other 3 tables?

I hope that made sense somewhat.

Thanks.

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