GroupTable::delete

static function delete($primary)
{
	$primary = Assert::expectIntegerPositive($primary, '$primary');

	$delResult = parent::delete($primary);

	// delete connected data
	if($delResult->isSuccess())
	{
		NameGroupTable::deleteMultipleForOwner($primary);
		GroupLocationTable::deleteByGroupId($primary);

		// set flag that indicates whether project still uses groups or not
		self::checkGroupUsage();
	}

	return $delResult;
}