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find('threaded', $params)

find('threaded', $params) returns a nested array, and is appropriate if you want to use the parent_id field of your model data to build nested results. Below are a couple of simple (controller code) examples:

function some_function() {
   ...
   $allCategories = $this->Category->find('threaded');
   $aCategory = $this->Category->find('first', array('conditions' => array('parent_id' => 42))); // not the root
   $someCategories = $this->Category->find('threaded', array(
	'conditions' => array(
		'Article.lft >=' => $aCategory['Category']['lft'], 
		'Article.rght <=' => $aCategory['Category']['rght']
	)
   ));
   ...
}

1. function some_function() {
2. ...
3. $allCategories = $this->Category->find('threaded');
4. $aCategory = $this->Category->find('first', array('conditions' => array('parent_id' => 42))); // not the root
5. $someCategories = $this->Category->find('threaded', array(
6. 'conditions' => array(
7. 'Article.lft >=' => $aCategory['Category']['lft'],
8. 'Article.rght <=' => $aCategory['Category']['rght']
9. )
10. ));
11. ...
12. }

It is not necessary to use the Tree behavior to use this method - but all desired results must be possible to be found in a single query.

In the above code example, $allCategories will contain a nested array representing the whole category structure. The second example makes use of the data structure used by the Tree behavior the return a partial, nested, result for $aCategory and everything below it. The results of a call to find('threaded') will be of the following form:

Array
(
    [0] => Array
        (
            [ModelName] => Array
                (
                    [id] => 83
                    [parent_id] => null
                    [field1] => value1
                    [field2] => value2
                    [field3] => value3
                )

            [AssociatedModelName] => Array
                (
                    [id] => 1
                    [field1] => value1
                    [field2] => value2
                    [field3] => value3
                )
            [children] => Array
                (
		    [0] => Array
			(
			    [ModelName] => Array
				(
				    [id] => 42
		                    [parent_id] => 83
				    [field1] => value1
				    [field2] => value2
				    [field3] => value3
				)

			    [AssociatedModelName] => Array
				(
				    [id] => 2
				    [field1] => value1
				    [field2] => value2
				    [field3] => value3
				)
		            [children] => Array
				(
				)
	                )
			...
                )
        )
)

The order results appear can be changed as it is influence by the order of processing. For example, if 'order' => 'name ASC' is passed in the params to find('threaded'), the results will appear in name order. Likewise any order can be used, there is no inbuilt requirement of this method for the top result to be returned first.

There are no additional parameters used by find('threaded').