基于thinkphp的左右值无限分类

以前一直使用父子无限分类,这种分类结构清晰,使用也简单。但若分类数量很大的话,在查询上性能不佳。比如在做导航菜单中,我要根据某一分类查询出整个分类树的话(祖辈)。

性能消耗是非常大的,要么做递归,要么做多次查询。故,对于分类的数据量很大的情况,我推荐使用左右值,以减少查询上的麻烦。

具体算法可以参照这里 :http://bbs.phpchina.com/viewthread.php?tid=92550&extra=&page=4

 


_id

    /**

         +----------------------------------------------------------
         * 构造函数
         * @access public
         * @return void
         +----------------------------------------------------------
         */

    public  function __construct($left,$right,$id){

        parent::__construct();
       $this->_left = $left;
       $this->_right = $right;
       $this->_id = $id;
    }

    /**

      +----------------------------------------------------------

      * 根据node$this->_id得到该node的所有值
      * @access public
      * @param $nodeId
      * @return array
      +----------------------------------------------------------

     */     

    public  function getNodeById($nodeId)

    {
        if($nodeId>0)
        {
            return $this->getById($nodeId);
        }

        else
        {

            throw_exception('未知$this->_id');
            return false;
        }

    }

    /**

           +----------------------------------------------------------

           * 获取父节点,含直属父类(type=1),所有父类:type=0

           * @access public 

           * @param $nodeId int 节点$this->_id

           * @return $parentNode array()

           +----------------------------------------------------------

          */     

    public  function getParentNode($nodeId,$type = 0)

    {

        if($nodeId == 0) throw_exception('未知$this->_id');;

        $currentNode = $this->getNodeById($nodeId);

        if($currentNode)

        {

            $condition = " ".$this->_left.'<'.$currentNode[$this->_left].' and '.$this->_right.' >'.$currentNode[$this->_right]." ";

            if($type ==1) //直属父类

            {

                return $this->where($condition)->order($this->_left." DESC")->limit(1)->find();

                //                $sql = "SELECT * FROM ".TABLE_NAME." WHERE {$condition} ORDER BY ".$this->_left." DESC LIMIT 1";

                //                return mysql_query($sql) or die(mysql_error());

            }

            else if($type ==0)

            {

                return $this->where($condition)->findAll();

                //                $sql = "SELECT * FROM ".TABLE_NAME." WHERE {$condition} ";

                //                return mysql_query($sql) or die(mysql_error());

            }

        }

        else

        {

            return false;

        }

    }

    /**

         +----------------------------------------------------------

         * 当前节点下子孙节点总数.子孙总数=(当前节点的右值 - 当前节点的左值-1)/2

         * @access public 

         * @param $node_id int 节点$this->_id

         * @return $amount int 该节点下的子孙总数         * 

         +----------------------------------------------------------

         */

    public  function getChildCount($nodeId)

    {

        $currentNode = $this->getNodeById($nodeId);

        if(!empty($currentNode))

        {

            return (int)($currentNode[$this->_right]-$currentNode[$this->_left] -1)/2;

        }

    }

    /**

      +----------------------------------------------------------

      * 获取当前节点下所有子节点。 当 A子类的右节点=B子类左节点-1 则 A、B属于同一级别

      * @access public 

      * @param $curentId

      * @param  $type int 0:当前节点下所有子类,1为当前节点下一级子类

      * @return bool

      +----------------------------------------------------------

     */     

    public  function getChild($nodeId,$type=0)

    {

        $currentNode = $this->getNodeById($nodeId);

        if($currentNode[$this->_left]-$currentNode[$this->_right] ==1)

        {

            return false; //当 该节点左值 - 右值=1  时,其下没有子节点。

        }

        else

        {

            $condition = $this->_left.'>'.$currentNode[$this->_left].' and '.$this->_right .'<'.$currentNode[$this->_right];

            $child = $this->where($condition)->findAll();

            if($type == 0)//所有子类

            {

                return $child;

            }

            else if($type ==1) //获取当前节点下一级分类

            {                        

                $subArr = array(); //一级子类

                foreach ($child as $k=>$sub) {

                    //子类的左节点=父类左节点+1,则子类为第一个子类

                    if($sub[$this->_left]==$currentNode[$this->_left]+1)

                    {

                        //$right = $sub[$k][$this->_right]; //当前节点的右节点

                        $firstSub = $sub; //当前节点下第一个子类

                        array_push($subArr,$firstSub); //子类入栈

                        unset($child[$k]);

                    }

                }

                $rightVal =  $firstSub[$this->_right]; //第一个子节点为比较标志

                $childCount = count($child);//剩余子节点数

                for($i=0;$i<$childCount;$i++) //循环检索出 同级子节点

                {

                    foreach ($child as $key => $sub2) {

                        if($rightVal == $sub2[$this->_left]-1)

                        {

                            $rightVal = $sub2[$this->_right]; //把循环当前的node的右节点当做比较值

                            array_push($subArr,$sub2);

                            unset($child[$key]);

                        }

                    }

                }

                return $subArr;

            }

        }

    }

    /**

         +----------------------------------------------------------

         * 返回当前节点的完整路径

         * @access public 

         * @param $nodeId

         * @return array

         +----------------------------------------------------------

        */     

    public  function getSinglePath($nodeId)

    {

        $sql = "select parent.* from __TABLE__ as node,__TABLE__ as parent where node.{$this->_left} between parent.{$this->_left}

            AND parent.{$this->_right} AND node.{$this->_id} = {$nodeId} order by parent.{$this->_left}";

//        echo $sql;

        return $this->query($sql);

    }

    /**

      +----------------------------------------------------------

      * 添加子节点,分3种:0:在当前节点下最后追加一个子节点;1:在当前节点下追加第一个子节点;2:在当前节点下的某个子节点后追加

      * @access public 

      * @param $currentId int 

      * @param $nodeName string 新节点名称      

      * @param $targetId int 追加到当前节点下子节点的指定节点后

      * @return bool

      +----------------------------------------------------------

     */    

    public  function addNode($nodeId,$newData,$type=0,$targetId=0)

    {

        if(empty($newData))

        {

            throw_exception('新分类不能为空');

        }

        $currentNode = $this->getNodeById($nodeId);

        switch ($type) {

            case 0:

                $leftNode  = $currentNode[$this->_right]; //新节点的左值为父节点的右值

                $rightNode = $leftNode+1;

                break;

            case 1:

                $leftNode = $currentNode[$this->_left]+1; //新节点的左值为父节点的左值+1

                $rightNode = $leftNode+1;

                break;

            case 2:

                $otherNode = $this->getNodeById($targetId);

                $leftNode = $otherNode[$this->_right]+1;

                $rightNode = $leftNode+1;

            default:

                break;

        }

//         $sql = "UPDATE ".TABLE_NAME." SET ".$this->_right."=".$this->_right."+2 WHERE ".$this->_right." >= ".$leftNode;

//        $sql2 = "UPDATE ".TABLE_NAME." SET ".$this->_left."=".$this->_left."+2 WHERE ".$this->_left.">".$leftNode;

        $this->setInc($this->_right,$this->_right.">=".$leftNode,2); //把所有右值大于新节点左值的节点的右值+2,注意效率

        $this->setInc($this->_left,$this->_left.">".$leftNode,2);   //把所有大于新节点的左值+2

        $newData[$this->_left] = (int)$leftNode;

        $newData[$this->_right] =(int) $rightNode;

        return $this->add($newData);

    }

    /**

         +----------------------------------------------------------

         * 删除节点

         * @access public 

         * @param type 操作类型,默认为0删除当前节点下的所有子节点,1为删除包括自身的节点

         * @param $nodeId int 要删除的$this->_id

         * @return bool

         +----------------------------------------------------------

        */     

    public  function rmNode($nodeId,$type =1)

    {

        $currentNode = $this->getNodeById($nodeId);

        if($type == 1) //删除包含自身的节点

        {

            $sql = "DELETE FROM __TABLE__ WHERE ".$this->_left.">= {$currentNode[$this->_left]} AND ".$this->_right."<= {$currentNode[$this->_right]}";

            $childCount = ($this->getChildCount($nodeId)+1)*2; //要更新的值

            $sql2 = "UPDATE  __TABLE__  SET ".$this->_right."=".$this->_right."-".$childCount." WHERE ".$this->_right.">".$currentNode[$this->_right];

            $sql3 = "UPDATE  __TABLE__  SET ".$this->_left."=".$this->_left."-".$childCount." WHERE ".$this->_left.">".$currentNode[$this->_left];

        }

        else //删除当前节点下的所有节点

        {

            $sql ="DELETE FROM __TABLE__ WHERE ".$this->_left."> {$currentNode[$this->_left]} AND ".$this->_right."< {$currentNode[$this->_right]}";

            $childCount = $this->getChildCount($nodeId)*2; //要更新的值

            $sql2 = "UPDATE __TABLE__ SET ".$this->_right."=".$this->_right ."-".$childCount." WHERE ".$this->_right.">=".$currentNode[$this->_right];

            $sql3 = "UPDATE __TABLE__ SET ".$this->_left."=".$this->_left."-".$childCount." WHERE ".$this->_left.">".$currentNode[$this->_left];

        }

         $this->execute($sql);  

         $this->execute($sql2);  

         $this->execute($sql3);  

        return true;

    }

     /**

      +----------------------------------------------------------

      * 修改节点,名称等

      * @access public 

      * @param $newData array()必须含有 要修改的$this->_id,k-v必须对齐,如arr['node_name'] = '商品'

      * @return bool

      +----------------------------------------------------------

     */     

    public  function modiNode($newData)

       {

            if(!empty($newData))

            {

                $id = $newData[$this->_id];                

                unset($newData[$this->_id]);

                return $this->save($newData,$this->_id.'='.$id);                               

          }

       }

}

?>

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