Problème controlleur post

Bonjour,
Voilà mon problème, je fais un site web, et là je suis sur l'administration et je rencontre un problème avec ma gestion des articles

Database Error
Error: SQLSTATE[42S22]: Column not found: 1054 Champ 'User.username' inconnu dans field list

SQL Query: SELECT `Post`.`id`, `Post`.`name`, `Post`.`slug`, `Post`.`created`, `Post`.`content`, `Category`.`slug`, `Category`.`name`, `User`.`username`, `Category`.`id` FROM `sitefin`.`posts` AS `Post` LEFT JOIN `sitefin`.`categories` AS `Category` ON (`Post`.`category_id` = `Category`.`id`) WHERE `type` = 'post' AND online >= 0 ORDER BY `Post`.`created` DESC, `Post`.`id` DESC LIMIT 5

Notice: If you want to customize this error message, create app\View\Errors\pdo_error.ctp

Stack Trace
CORE\Cake\Model\Datasource\DboSource.php line 461 ? PDOStatement->execute(array)
CORE\Cake\Model\Datasource\DboSource.php line 427 ? DboSource->_execute(string, array)
CORE\Cake\Model\Datasource\DboSource.php line 669 ? DboSource->execute(string, array, array)
CORE\Cake\Model\Datasource\DboSource.php line 1108 ? DboSource->fetchAll(string, boolean)
CORE\Cake\Model\Model.php line 3022 ? DboSource->read(Post, array)
CORE\Cake\Model\Model.php line 2994 ? Model->_readDataSource(string, array)
CORE\Cake\Controller\Component\PaginatorComponent.php line 196 ? Model->find(string, array)
CORE\Cake\Controller\Controller.php line 1086 ? PaginatorComponent->paginate(string, array, array)
APP\Controller\PostsController.php line 99 ? Controller->paginate(string, array)
[internal function] ? PostsController->admin_index()
CORE\Cake\Controller\Controller.php line 490 ? ReflectionMethod->invokeArgs(PostsController, array)
CORE\Cake\Routing\Dispatcher.php line 193 ? Controller->invokeAction(CakeRequest)
CORE\Cake\Routing\Dispatcher.php line 167 ? Dispatcher->_invoke(PostsController, CakeRequest)
APP\webroot\index.php line 57 ? Dispatcher->dispatch(CakeRequest, CakeResponse)

Mais ce champ est déjà dans ma BDD donc je pense que ca viens de mon PostController.php (voir ci-dessous)

PostController.php :

<?php
class PostsController extends AppController{

    public $paginate = array(
        'fields'  => array('Post.id','Post.name','Post.slug','Post.created','Post.content','Category.slug','Category.name','User.username'),
        'contain' => array('Category','User'),
        'limit'   => 5,
        'paramType' => 'querystring'
    );
    public $helpers = array('Date','Markdown.Markdown');
    public $components = array('RequestHandler');

    function index(){
        $conditions = null;

        // Category filter
        if(isset($this->request->params['category'])){
            $conditions = array('Category.slug' => $this->request->params['category']);
            $this->request->params['named']['category'] = $this->request->params['category'];
        }
        if(isset($this->request->params['user'])){
            $conditions = array('Post.user_id' => $this->request->params['user']);
            $this->request->params['named']['user'] = $this->request->params['user'];
        }

        $d['posts'] = $this->Paginate('Post',array('type'=>'post','online'=>1,'created <= NOW()'));
        $this->set($d);
    }

    function view($id = null,$slug = null){
        $this->Post->contain('Category', 'User', 'Comment');
        //$post = $this->Post->findBySlug($slug, array('Post.name','Post.slug','Post.created','Post.content','Category.slug','Category.name','User.username'));
        if(!$id)
            throw new NotFoundException('Aucunes pages ne correspond à cet ID');
        $post = $this->Post->find('first',array(
            'conditions' => array('Post.id' => $id,'Post.name','Post.slug','Post.created','Post.content','Category.slug','Category.name','User.username'),
            'recursive' => 0
            ));
        if(empty($post))
            throw new NotFoundException('Aucunes pages ne correspond à cet ID');

        if($slug != $post['Post']['slug'])
            $this->redirect($post['Post']['link'],301);
        $d['post'] = $post;
        $this->set($d);

        // Comment submission
        if(!empty($this->request->data)){
            $this->Post->Comment->create($this->request->data, true);
            $this->request->data['Comment']['post_id'] = $post['Post']['id'];
            if($this->Post->Comment->save(null, true, array('mail', 'username', 'content', 'post_id'))){
                $this->Session->setFlash("Thanks for your comment","success");
                return $this->redirect($this->referer());
            }else{
                $this->Session->setFlash("You have to correct your errors first","error");
            }
        }
    }

    /**
    * Requested, get datas for sidebar
    **/
    public function sidebar(){
        $last_posts = $this->Post->find('all', array(
            'limit' => 2,
            'fields'=> array('Post.id','Post.slug','Post.name')
        ));
        $categories = $this->Post->Category->find('all');
        return compact('last_posts', 'categories');
    }

    function feed(){
    if ($this->RequestHandler->isRss() ) {
        $d['posts'] = $this->Post->find('all', array(
            'limit' => 20,
            'conditions' => array('type'=>'post')
            ));
        return $this->set($d);
        }
    } 

    function category($category){
        $cat = $this->Post->Category->find('first',array(
            'conditions' => array('slug' => $category)
        ));
        if(empty($cat))
            throw new NotFoundException('Aucunes catégorie ne correspond à cet ID');
        $d['posts'] = $this->Paginate('Post',array('type'=>'post','online >= 0','category_id' => $cat['Category']['id']));
        $this->set($d);
        $this->render('index');

    }

    /**
    * Admin panel
    **/
    function admin_index(){
        $d['posts'] = $this->Paginate('Post',array('type'=>'post','online >= 0'));
        $this->set($d);
    }

    function admin_edit($id = null){
        if($this->request->is('put') || $this->request->is('post')){
            if($this->Post->save($this->request->data)){
                $this->Session->setFlash("L'article a bien été sauvegardé","notif");
                $this->redirect(array('action'=>'index'));
            }

        }elseif($id){
            $this->Post->id = $id;
            $this->request->data = $this->Post->read(); 
        }else{
            $this->request->data = $this->Post->getDraft('post');
        }
        $d['categories'] = $this->Post->Category->find('list');
        $this->set($d);
    }

    public function admin_delete($id){
        $this->Post->delete($id);
        $this->Session->setFlash('La page a bien été supprimée','notif');
        $this->_clean_cache();
        $this->redirect($this->referer());
    }

    private function _clean_cache(){
        if(file_exists(CACHE . 'cake_element__sidebar_cache_callbacks')){
            unlink(CACHE . 'cake_element__sidebar_cache_callbacks');
        }
    }

}

Merci d'avance !