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CakePHP and composite primary keys

Today, I was doing some comprehensive research about CakePHP framework, as a part of our web application framework research. I installed it and developed a sample application following the official documentation. Some interesting facts were found. And, here, I am listing down few of the advantages and disadvantages of this framework in relation to our existing systems.

CakePHP has many good characteristics such as easy configuration, easy installation, light weight etc. And also, it's a excellent RAD tool, and it will save development time in a great margin. The database tasks can be done without writing one single sql query. And, CakePHP can be used with or without apache rewrite module, there is a clean url mechanism inside the framework instead of url rewriting.

Naming convention is very important in CakePHP. Database tables should have the same name as the relevant model classes. For example, by naming the model "Orange", CakePHP can automatically infer that this model will be used in the "OrangeController", and will be tied to a database table called "Oranges".

Composite primary keys can't be used for data base tables. Even if composite primary keys are kept in the tables, those are not used by the framework. Framework uses only one field as the primary key. If you want to use composite primary keys, you should hand write all the queries related to that task.

Alternatively, If we want to add a existing table that have two fields which compose the primary key, then what we have to do is we should add a new 'id' field as the primary key, and that field will be used by framework, we can make the other two fields (previous composite primary keys) as unique keys.

After all, the fact that the composite primary keys can't be used with CakePHP is clearly mentioned in the official documentation as well.


  1. Of course, cakePHP is an excellent framework. Most importantly it provides a facility called 'cake bake', you can automatically create your views, controllers and models with it.
    Your observation regarding composite primary keys is correct. Database should be carefully designed avoiding composite primary keys if you are using the cakePHP framework. I've done that in many cakePHP applications.


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