Doctrine query with ManyToMany relation - sql

Question

I have a simple relation ManyToMany between two entities "article" and "category" (for a blog). I would like to fetch every article with a particular category, but I don't know how to create that query. What I did is :
$query = $em->createQuery(
'SELECT u
FROM SiteBlogBundle:article u
WHERE u.categorie.name = :cat
ORDER BY u.date DESC'
)
->setParameter('cat', '$cateogory')
The line WHERE u.categorie.name = :cat doesn't work. How can I achieve that?

Answer 1

If you are okay with using a query-builder for better readability instead of DQL:
$articles = $em
->getRepository('SiteBlogBundle:Article')
->createQueryBuilder('article')
->leftJoin('article.category', 'category')
->where('category.name = :category_name')
->orderBy('article.date', 'DESC')
->setParameter('category_name', $category->getName())
->getQuery()
->getResult()
;
But i would strongly advise you to put this query into the repository like this:
// ArticleRepository.php
public function findArticlesByCategoryName($name)
{
return $this->createQueryBuilder('article')
->leftJoin('article.category', 'category')
->where('category.name = :category_name')
->orderBy('article.date', 'DESC')
->setParameter('category_name', $name)
->getQuery()
->getResult()
;
}
Then inside your controller just do:
public function getArticles(Category $category)
{
$em = $this->getDoctrine()->getEntityManager();
return $em->
getRepository('SiteBlogBundle:Article')
->findArticlesByCategoryName($category->getName())
;
}