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POPHP MySQL table inheritance
 

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    <p>I am implementing two objects, say HotDog and Burger, and they are both subclass of Food.</p> <p>The system I am working on will be used to create HotDog and Burger, potentially other types of Food, <strong>but never will it be used to created a generic "Food" object.</strong></p> <p>Food</p> <pre><code>class Food{ //some fields protected $cooked_by; protected $use_before_date; } </code></pre> <p>HotDog:</p> <pre><code>class HotDog extends Food{ //some fields specicifc to HotDog private $sauage_type; } </code></pre> <p>Burger</p> <pre><code>class Burger extends Food{ //some fields specicifc to Burger private $burger_type; } </code></pre> <p>These models have a corresponding DB Table, namely Food, HotDog and Burger.</p> <p>How if I want to select all HotDog cooked by a certain chief, currently I have to loop through every single row of HotDog like this:</p> <p><code>SELECT food_id FROM hotdog</code></p> <p>Then loop through the entire resultset, for each row doing:</p> <p><code>SELECT * FROM food WHERE food_id = x AND cooked_by=chief0001</code></p> <p>I hope you understand the structure I am trying to build here. Currently having to obtain all food_id for each HotDog row, then select from the food table one-by-one is a serious performance hit.</p> <p>It would be nice to be able to just do :</p> <p><code>SELECT * FROM hotdog WHERE cooked_by = chief0001</code></p> <p>However as you can see, the current way of implementing the Models and the Tables does not allow me to do this. Surely I can add another column to the HotDog and Burger tables, however, should I need to query anything other than cooked_by, I will have to add yet another column to both tables.</p> <p>Eventually, I will just add all the columns in the Food table into HotDog and Burger.</p> <p>Is that the right way to do table inheritance ? I feel like something isn't right here, and there should be a cleaner and better solution. However I am pulling my hair trying to come up with a good way of overcoming this.</p>
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