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Data Model Questions

Issue with DataExtension and $many_many


2 Posts   305 Views


12 January 2014 at 5:46pm Community Member, 1 Post

Hi guys,

I've got an issue that I'm hoping someone can help with.

I've set up a DataExtension called BlogEntryExtension, which is applied to BlogEntry. I've also got a custom DataObject of class BlogCategory. So far so good.

BlogEntryExtension adds
$many_many = array('BlogCategories' => 'BlogCategory');

BlogCategory contains
$belongs_many_many = array('BlogEntries' => 'BlogEntry');

The idea being that a BlogEntry can belong to many categories, and a category can contain multiple BlogEntries.

My issue is twofold. Firstly, I assumed that $this->owner->BlogCategories() from within BlogEntryExtension would return me the related BlogCategories. It doesn't - it returns ALL BlogCategories in the database.

Secondly, when I create a GridField Relation Editor for this relationship, it doesn't reflect the relationship, instead showing ALL BlogCategories again.

Has anyone encountered this before? Is many_many within DataExtensions not supported, or have I just misused something?

Thanks in advance.


18 January 2014 at 11:27am Forum Moderator, 5511 Posts

many_many should be supported in extensions fine and $this->owner->BlogCategories() should get you just the relations. There isn't a method called BlogCategories on your BlogEntry or any extensions that is overriding the SilverStripe __get() is there?