silverstripe-framework/tests/php/ORM/VersionedOwnershipTest/Attachment.php

<?php

namespace SilverStripe\ORM\Tests\VersionedOwnershipTest;

use SilverStripe\Dev\TestOnly;
use SilverStripe\ORM\DataObject;
use SilverStripe\ORM\Versioning\Versioned;

/**
 * @mixin Versioned
 */
class Attachment extends DataObject implements TestOnly
{

    private static $extensions = array(
        Versioned::class,
    );

    private static $table_name = 'VersionedOwnershipTest_Attachment';

    private static $db = array(
        'Title' => 'Varchar(255)',
    );

    private static $belongs_many_many = array(
        'AttachedTo' => 'SilverStripe\\ORM\\Tests\\VersionedOwnershipTest\\Related.Attachments'
    );

    private static $owned_by = array(
        'AttachedTo'
    );
}