R – zend models architecture

It's a bit tough to give you the "right" answers, since some of them deal with the specifics of the framework (regardless of the ones you are working with).

At least in terms of CakePHP:

1. Yes

2. Anything that deals with data or data manipulation should be in a model. In terms of CakePHP what about a simple find() method? ... If there is a chance that it will do something "special" (i.e. recall a specific set of 'condition'), which you might need elsewhere, that's a good excuse to wrap inside a model's method.

3. Unfortunately there is never an easy answer, and refactoring of the code is a natural process. Sometimes you just wake up an go: "holy macaroni... that should be in the model!" (well maybe you don't do that, but I have :))

There are a few things to fix up here, but here are a few tips.

i. Table models work a little better if their names are pluralized. They sound better in the magic methods (e.g. $product_set = findProducts() instead of findModel_Product())

ii. The reference map is the important one and allows for those nifty magic selection methods (e.g. findParentX()) to work. It belongs in the dependent table, which is the product table here because it references the product_manufacturer.

  // in Model_Product
  protected $_referenceMap = array(

    // rule name
    'Manufacturer' => array(

      'columns'       => 'manufacturer_id',     // this column
      'refTableClass' => 'Model_Manufacturer',  // references that table object
      'refColumns'    => 'id'                   // and references that column
    )
  );

iii. Move dependent tables entry to your product_manufacturers table model, if you'd like: it's used only to replicate ON DELETE/UPDATE CASCADE database commands, though. (Leave it for now)

// in manufacturer table model
protected $_dependentTables = array('Model_Product');

Fetching

To get a product's manufacturer, do this:

$manufacturer = $product_row->findParentManufacturer();

To get a manufacturer's products, do this:

$product_set = $manufacturer_row->findProducts(); // Well, findModel_Product(), which is why you should rename your table ;)

For other magic methods originating from each single row, dig into the source code for Zend_Db_Table_Row_Abstract (especially public function __call).