silverstripe-framework/tests/php/ORM/DataObjectTest/Team_Extension.php

<?php

namespace SilverStripe\ORM\Tests\DataObjectTest;

use SilverStripe\Dev\TestOnly;
use SilverStripe\ORM\DataExtension;

class Team_Extension extends DataExtension implements TestOnly
{
	private static $db = array(
		'ExtendedDatabaseField' => 'Varchar'
	);

	private static $has_one = array(
		'ExtendedHasOneRelationship' => Player::class
	);

	public function getExtendedDynamicField()
	{
		return "extended dynamic field";
	}

}