Symfony Doctrine ORM ManyToMany - 带标签的博客 - 我没有从博客中获取所有标签，没有延迟加载

Question

Doctrine lazy loading on manyToMany.

I'm using Application\Sonata\ClassificationBundle\Entity\Tag in my blog(post).

/**
     * @var string
     *
     * @ORM\ManyToMany(targetEntity="\Application\Sonata\ClassificationBundle\Entity\Tag", cascade={"persist"} )
     * @ORM\JoinTable( name="blog__post_tag" , 
     * joinColumns={ @ORM\JoinColumn( name="blog_post_id", referencedColumnName="id" )},
     * inverseJoinColumns={ @ORM\JoinColumn( name="tag_id", referencedColumnName="id" )}
     * )
     */
    private $tags;

Working code:

$q = $this->createQueryBuilder('p')
                ->select('p')
                ->innerJoin('p.tags', 't')
                ->where('t = :name')->setParameter('name', $tag)
                ->andWhere('p.isActive = :active')->setParameter('active', TRUE)
                ->orderBy('p.id', 'DESC');
        return $q->getQuery();

From this output query i use tags in twig. So i have to select post and tags. If i update the code to :

$q = $this->createQueryBuilder('p')
                ->select('p', 't')
                ->innerJoin('p.tags', 't')
                ->where('t = :name')->setParameter('name', $tag)
                ->andWhere('p.isActive = :active')->setParameter('active', TRUE)
                ->orderBy('p.id', 'DESC');
        return $q->getQuery();

I get only one tag.

INFO :

• Working code uses more db query (1 more query).
• Updated code works (no more query). But in result i get only one tag for all post.

Example :

• "My First post " has tags ['one','two','three'].
• "My Second post " has tags ['two'].

When i use first query. Works fine. But the doctrine lazy load code for tags. I get output for (query1) two = "My First post " has tags ['one','two','three']. , "My Second post " has tags ['two'].

When i use second query. The output for (query2) two = "My First post " has tags ['two']. , "My Second post " has tags ['two'].

I need all tags from the post. Currently i get only one tag form the post.

Answer 1

It's like that because of INNER JOIN. Great answer about join types is here: https://stackoverflow.com/a/6188334/919567

This version of query will work for you:

$q = $this->createQueryBuilder('p')
    ->select('p', 't')
    ->leftJoin('p.tags', 't')
    ->where('t = :name')->setParameter('name', $tag)
    ->andWhere('p.isActive = :active')->setParameter('active', TRUE)
    ->orderBy('p.id', 'DESC');

return $q->getQuery();