recursiveプロパティを-1に設定する。(Cakeは当該モデルのデータだけを取得します。joinしません。)
$this->Post->recursive = -1;
$posts = $this->Post->find('all');
または、
$posts = $this->Post->find('all', array(
'recursive' => -1,
'conditions' => ...
);
参考
モデルの属性
http://book.cakephp.org/2.0/ja/models/model-attributes.html#recursive
Retrieving models without getting associated models - CakePHP
http://stackoverflow.com/questions/5575884/retrieving-models-without-getting-associated-models-cakephp