Question

我使用nested set在Symfony2中使用StofDoctrineExtension行为。

类别和帖子模型配置得很好，类别树工作正常。

要显示某个类别的帖子，我将从我的存储库中使用此查询：

public function findAllPosts($category)
{
    return $this->queryAllPosts($category)->getResult();
}

public function queryAllPosts($category)
{
    $em = $this->getEntityManager();

    $query = $em->createQuery('
        SELECT p, c FROM AppBundle:Post p JOIN p.category c
        WHERE c.slug = :category
        ORDER BY p.created DESC
    ');

    $query->setParameter('category', $category);

    return $query;
}

但是我怎样才能显示这些类别的孩子的帖子呢？

Answer 1

你应该能够在一个接近这一个的查询中做到这一点，因为我不是专业SQL，它通常需要我时间和测试才能做到正确但这是我要开始的地方：

 SELECT parent.* , children.* FROM 
          (SELECT p, c FROM AppBundle:Post p JOIN p.category c WHERE c.slug = :category) AS parent 
          INNER JOIN 
          (SELECT p1 FROM  AppBundle:Post p1 JOIN p.category c1 ON c1.parent = parent.id ) AS children

不确定是否需要在内部选择内部执行ON或者为连接选择包装器，但您可以尝试：）

Answer 2

如果CategoryRepository继承自NestedTreeRepository，您可以执行以下操作：

$categories = $em->getRepository('XBundle:Category')
  ->childrenQueryBuilder($category)
  ->addSelect('posts')
  ->join('node.posts', 'posts')
  ->getQuery()
  ->getResult();

foreach ($categories as $category) {
  $category->getPosts();
  // do stuff
}

Answer 3

我找到了方法。查询将是这样的：

/*
 * GET POSTS FROM PARENT AND CHILDREN
 */
public function getPostsParentAndChildren($children)
{
    $em = $this->getEntityManager();

    $posts = $em->createQueryBuilder()
        ->select(array('p', 'c'))
        ->from('AppBundle:Post', 'p')
        ->join('p.category', 'c')
        ->where('c.id IN (:children)')
        ->orderBy('p.created', 'DESC')
        ->getQuery();

    $posts->setParameter('children', $children);

    return $posts->getResult();
}

我们将带有子节点的数组传递给查询，我们使用函数getChildren（$ categoryId）获取该数组。请记住，您必须传递id（使用此查询），因此您可以获得这样的ID：

    $category = $repo->findOneBy(array('slug' => $slug1));

    $children = $repo->getChildren($category);

    $childrenIds[] = $category->getId();
    foreach ($children as $child){
        $id = $child->getId();
        $childrenIds[] = $id;
    }

    $posts = $em->getRepository('AppBundle:Category')->getPostsParentAndChildren($childrenIds);

使用Doctrine Extensions Tree Nested set在父母中获取孩子的帖子

3 个答案: