I have a simple Category model in my CakePHP application. I want to add sub-categories, and do this by simply adding a parent_id column.
The parent_id is a belongsTo relationship, that references back to the same Category model.
When I generate my admin scaffolds, a dropdown will shop up (correct!), but I'd like to include a NULL option in this dropdown (for top-level categories).
Is this possible? And if so, how..
(Note: not interested in Tree behaviour right now)
Sounds like you may be looking for the empty option:
<?php echo $form->input(
'field',
array( 'options' => array( 1, 2, 3, 4, 5),
'empty' => 'Select one'
); ?>