Q:

Symfony2 - Need help on the following error when querying for tags

Having the following error in my doctrine query when trying to find a specific tag selected by the user.
[Semantical Error] line 0, col 78 near 'tag WHERE blog.tags': Error: Class Acme\DemoBundle\Entity\Blog has no association named tags
Can someone tell what's wrong with the query? (trying to query for a tag selected in the side bar that brings up all posts related to the tag)
Repository
public function getPostsByTags($tags)
{
    $qb = $this->createQueryBuilder('b');
    $qb->select('b')
        ->join('b.tags', 'tag')
        ->where('b.tags LIKE ?', '%'.$tags.'%');

    return $qb->getQuery()->getResult();

}

Blog Entity
/**
 * @var string
 *
 * @ORM\Column(name="tags", type="text")
 */
private $tags;

/**
 * Set tags
 *
 * @param string $tags
 * @return Blog
 */
public function setTags($tags)
{
    $this->tags = $tags;

    return $this;
}

/**
 * Get tags
 *
 * @return string
 */
public function getTags()
{
    return $this->tags;
}

Controller
/**
 * @Route("/tag/{tag}", name="AcmeDemoBundle_tag")
 * @Template("AcmeDemoBundle:Page:tag.html.twig")
 */
public function tagAction($tag = null)
{
    $em = $this->getDoctrine()->getManager();

    $tags = $em->getRepository('AcmeDemoBundle:Blog')
        ->getPostsByTags($tag);

    if (!$tags) {
        throw $this->createNotFoundException('Unable to find blog posts');
    }

    return array(
        'tags'  => $tags,
    );
}

Sidebar Twig
<p class="tags">
    {% for tag, weight in tags %}
    <span class="weight-{{ weight }}"><a href="{{ path('AcmeDemoBundle_tag', { 'tag': tag }) }}">{{ tag }}</a></span>
    {% else %}
<p>There are no tags</p>
{% endfor %}
</p>

Tag results twig
{% block body %}
{% for tag in tags %}
    <article class="result">
        <div class="date"><time datetime="{{ tag.created|date('c') }}">{{ tag.created|date('l, F j, Y') }}</time></div>
        <header>
            <h2><a href="{{ path('AcmeDemoBundle_show', { 'id': tag.id, 'slug': tag.slug }) }}">{{ tag.title }}</a></h2>
        </header>

        <img src="{{ asset(['images/', tag.image]|join) }}" />
        <div class="snippet">
            <p>{{ tag.blog|truncate(250, true) }}</p>
            <p class="continue"><a href="{{ path('AcmeDemoBundle_show', { 'id': tag.id, 'slug': tag.slug }) }}">More...</a></p>
        </div>

        <footer class="meta">
            <p>Comments: -</p>
            <p>Posted by <span class="highlight">{{tag.author}}</span> at {{ tag.created|date('h:iA') }}</p>
            <p>Tags: <span class="highlight">{{ tag.tags }}</span></p>
        </footer>
    </article>
{% else %}
    <p>There are no blog entries for Health&Fitness blog</p>
{% endfor %}
{% endblock %}

Updated solution: repository query (no blogs found)
public function getPostsByTags($tags)
{

    $query = $this->createQueryBuilder('b')
        ->where('b.tags = :tags')
        ->setParameter('tags', $tags);

    return $query->getQuery()->getResult();
}

Updated solution: controller using query (no blogs found)
public function tagAction(tags=null)
{
    $em = $this->getDoctrine()->getManager();

    $repository = $em->getRepository('AcmeDemoBundle:Blog');

    $tags = $repository->createQueryBuilder('b')
        ->where('b.tags = :tags')
        ->setParameter('tags', $tags)
        ->getQuery()
        ->getResult();

    return array(
        'tags' => $tags,
    );
}

A:

Change your getPostsByTags function to:
$repository = $this->getDoctrine()
    ->getRepository('AcmeDemoBundle:Blog');

$query = $repository->createQueryBuilder('b')
->where('b.tags = :tags')
->setParameter('tags', $tags)
->getQuery();

return $query->getResult();

