private function _prepareJoinCondition(array $condition)
	{
		if(count($condition) === 1)
		{
			return $this->condition = '(' . $condition[0]->getColumnName() . ')';
		}

		return $this->condition =
			$condition[0]->getTableName() . '.' . $condition[0]->getColumnName() . ' = ' . $condition[1]->getTableName()
			. '.' . $condition[1]->getColumnName();
	}