public function createCommand($builder)
	{
		$sql=($this->distinct ? 'SELECT DISTINCT ':'SELECT ') . implode(', ',$this->selects);
		$sql.=' FROM ' . implode(' ',array_unique($this->joins));

		$conditions=array();
		foreach($this->conditions as $condition)
			if($condition!=='')
				$conditions[]=$condition;
		if($conditions!==array())
			$sql.=' WHERE (' . implode(') AND (',$conditions).')';

		$groups=array();
		foreach($this->groups as $group)
			if($group!=='')
				$groups[]=$group;
		if($groups!==array())
			$sql.=' GROUP BY ' . implode(', ',$groups);

		$havings=array();
		foreach($this->havings as $having)
			if($having!=='')
				$havings[]=$having;
		if($havings!==array())
			$sql.=' HAVING (' . implode(') AND (',$havings).')';

		$orders=array();
		foreach($this->orders as $order)
			if($order!=='')
				$orders[]=$order;
		if($orders!==array())
			$sql.=' ORDER BY ' . implode(', ',$orders);

		$sql=$builder->applyLimit($sql,$this->limit,$this->offset);
		$command=$builder->getDbConnection()->createCommand($sql);
		$builder->bindValues($command,$this->params);
		return $command;
	}