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POHow to find a given value in a many-to-many relationship using Doctrine?
 

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  1. POHow to find a given value in a many-to-many relationship using Doctrine?
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    <p>I have an entity "Discussion" that has (among other things):</p> <ul> <li>A category property (every discussion has 1 category associated with it)</li> <li>A ManyToMany association of "recommended categories" (every discussion can be recommended in multiple categories)</li> </ul> <p>I'm trying to select all the discussions that are either in a specific category (their category property is that category) or that are recommended in this specific category.</p> <p>I can easily get all the discussions that are in this category like this:</p> <pre><code> $qb = self::$em-&gt;getRepository('Discussion')-&gt;createQueryBuilder('d'); $discussions = $qb-&gt;where('d.category='.$current_category_id) -&gt;setFirstResult( $offset ) -&gt;setMaxResults( $limit ) -&gt;getQuery()-&gt;getResult(); </code></pre> <p>I need to add to that all the discussions that have current_category_id in their list of recommended_categories.</p> <p>So adding something like this:</p> <pre><code>$qb = self::$em-&gt;getRepository('Discussion')-&gt;createQueryBuilder('d'); $discussions = $qb-&gt;where('d.category='.$current_category_id) -&gt;orWhere($qb-&gt;expr()-&gt;in($current_category_id, 'd.recommended_categories')) -&gt;setFirstResult( $offset ) -&gt;setMaxResults( $limit ) -&gt;getQuery()-&gt;getResult(); </code></pre> <p>Which gives an SQL error because it doesn't like the "4 IN(d.recommended_categories))" in the SQL.</p> <p>This is what the recommended_categories looks like in the Discussions entity:</p> <pre><code>/** * @ManyToMany(targetEntity="Category") * @JoinTable(name="discussion_recommended_categories", * joinColumns={@JoinColumn(name="discussion_id", referencedColumnName="id")}, * inverseJoinColumns={@JoinColumn(name="category_id", referencedColumnName="id")} * ) */ private $recommended_categories; </code></pre> <p>And here is the Category entity:</p> <pre><code>/** @Id @Column(type="integer") @GeneratedValue **/ protected $id; /** @Column(type="string", unique=true, nullable=false,name="Name") **/ protected $name; </code></pre> <p>I also tried playing around with exists (does $current_category_id exist in d.recommended_categories) but nothing worked.</p> <p><strong>Any ideas how I can check if a given value (not a column) exists in a list of values associated with that entity?</strong></p> <p>Thanks!</p>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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