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Question

I'm trying make an entity with doctrine that has three associations with other entities

So an Item is associated with:

• Must be associated with One Rssfeed, which it originates from
• Can be associated with One or more Locations
• Can be associated with one or more Tags

Here is my attempt:

class Item{

    /**
     * @ManyToOne(targetEntity="Rssfeed")
     */
    protected $rssfeed;

    /**
     *
     * @ManyToMany(targetEntity="Location")
     */
    protected $locations;

    /**
     *
     * @ManyToMany(targetEntity="Tag")
     */
    protected $tags;
}

Now

• If an Rssfeed is removed, associated items must be removed too
• If an item is removed, Rssfeeds, and Locations, and Tags attached to that item should be detached
• If a Location, or Tag is removed, the associated items should just be detached, because they are optional associations.

How should I change my code to accomplish that?

Answer 1

U have to add @JoinColumn with onDelete="CASCADE" for $rssfeed and onDelete="SET NULL" for foreign keys in Location and Tag entities.

    /**
     * @ManyToOne(targetEntity="Rssfeed")
     * @JoinColumn(name="rssfeed_id", referencedColumnName="id", onDelete="CASCADE")
     */
    protected $rssfeed;

Answer 2

For each association in your Item entity, add onDelete="SET NULL" to the @JoinColumn annotation. Inside your location and tag entities, find the JoinColumn annotations and add onDelete="SET NULL" for the association with "Item". Under the RssFeed entity, find each @JoinColumn annotation and add onDelete="SET NULL". Note that you can also use Doctrine cascade operations to achieve this (ie cascade={"remove"}, etc; however, it will likely be significantly slower as the operating is not performed at the RDBMS level.