无限级分类的非递归实现(存储过程版）

或多或少都做过树状目录、产品分类之类的二级或三级菜单，如果遇到更多级的分类，就一般使用递归了。在程序中使用递归或多或少会增加一些性能上的开销。

之前我用ASP.net在程序中实现过非递归的无限级分类目录，但考虑到移植性不强，就改成了存储过程，发出来大家共同研究一下，到目前为止，测试过程中还没发现问题，另外，代码方面没经过什么优化。

通常情况下，我们更多的操作是读取目录，所以，在下面的实现中，读取我们只需要一Select语句就够了,不使用递归，理论上无限级~！
======================================================================
表结构：
表名：Tb_Column
表结构（所有字段非空）：
Column_ID     int 主键（注：非标识）
Column_Name   nvarchar(50)分类名称
Parent_ID     int 父分类ID（默认值0）
Column_Path   nvarchar(1000) 分类路径
Column_Depth  int分类深度(默认值0）
Column_Order  int排序(默认值0)
Column_Intro  nvarchar(1000)分类说明

=============================================================
存储过程一：新建分类

CREATE PROCEDURE sp_Column_Insert
(
@Parent_ID int,
@Column_Name nvarchar(50),
@Column_Intro nvarchar(1000)
)
AS
Declare @Err As int
Set @Err=0

Begin Tran
--通过现有记录获取栏目ID
Declare @Column_ID As int
Declare @Column_Depth As int
Select @Column_ID = Max(Column_ID) From Tb_Column
IF @Column_ID Is Not Null
Set @Column_ID = @Column_ID+1
Else
Set @Column_ID = 1

--判断是否是顶级栏目，设置其Column_Path和Column_Order
Declare @Column_Path As nvarchar(1000)
Declare @Column_Order As int
IF @Parent_ID = 0
Begin
Set @Column_Path =Ltrim(Str(@Column_ID))
Select @Column_Order = Max(Column_Order) From Tb_Column
IF @Column_Order Is Not Null
Set @Column_Order = @Column_Order + 1
Else --如果没有查询到记录，说明这是第一条记录
Set @Column_Order = 1

--深度
Set @Column_Depth = 1
End
Else
Begin
--获取父节点的路径和深度
Select @Column_Path = Column_Path ,@Column_Depth = Column_Depth From Tb_Column Where

Column_ID=@Parent_ID
IF @Column_Path Is Null
Begin
Set @Err = 1
Goto theEnd
End

--获取同父节点下的最大序号
Select @Column_Order = Max(Column_Order) From Tb_PicColumn Where Column_Path like

''+@Column_Path+'|%'  Or Column_ID = @Parent_ID
IF @Column_Order Is Not Null --如果序号存在，那么将该序号后的所有序号都加1
Begin
--更新当前要插入节点后所有节点的序号
Update Tb_Column Set Column_Order = Column_Order +1 Where Column_Order

>@Column_Order
--同父节点下的最大序号加上1，构成自己的序号
Set @Column_Order = @Column_Order + 1
End
Else
Begin
Set @Err=1
Goto theEnd
End

--父节点的路径加上自己的ID号，构成自己的路径
Set @Column_Path = @Column_Path + '|' + Ltrim(Str(@Column_ID))

--深度
Set @Column_Depth = @Column_Depth+1

End

Insert Into Tb_Column(Column_ID,Column_Name,Parent_ID,Column_Path,Column_Depth,Column_Order,Column_Intro)

Values(@Column_ID,@Column_Name,@Parent_ID,@Column_Path,@Column_Depth,@Column_Order,@Column_Intro)

IF @@Error<>0
Begin
Set @Err=1
Goto theEnd
End

--更新当前记录之后的记录的ORDER
--Update Tb_Column Set Column_Order = Column_Order+1 Where Column_Order  > @Column_Order

theEnd:
IF @Err=0
Begin
Commit Tran
Return @Column_ID
End
Else
Begin
    Rollback Tran
Return 0
End
GO

=============================================================================
存储过程二：删除分类
CREATE PROCEDURE sp_Column_Delete
(
@Column_ID int
)
AS
Declare @Err As int
Set @Err = 0
Begin Tran
--首先查询该节点下是否有子节点
Select Column_ID From Tb_Column Where Parent_ID = @Column_ID
IF @@RowCount<>0
    Begin
    Set @Err = 1
    Goto theEnd
    End

--获取该节点的Column_Order,为了删除后整理其他记录的顺序
Declare @Column_Order As int
Select @Column_Order = Column_Order From Tb_Column Where Column_ID = @Column_ID
IF @Column_Order Is NUll
    Begin
      Set @Err =2
      Goto theEnd
    End

--更新其他记录的Column_Order
Update Tb_Column Set Column_Order = Column_Order -1 Where Column_Order >@Column_Order
IF @@Error<>0
    Begin
      Set @Err =3
      Goto theEnd
    End

--删除操作
Delete From Tb_Column Where Column_ID=@Column_ID
IF @@Error<>0
    Begin
      Set @Err =4
      Goto theEnd
  End

--更新其他记录的Column_ID
--Update Tb_Column Set Column_ID= Column_ID - 1 Where Column_ID >@Column_ID
--IF @@Error<>0
--    Begin
--      Set @Err =5
--      Goto theEnd
--    End

theEnd:
IF @Err = 0
    Begin
      Commit Tran
      Return 0 --删除成功
    End
Else
    Begin
      IF @Err=1
  Begin
      Rollback Tran
      Return 1 --有子节点
End
      Else
Begin
      Rollback Tran
      Return 2--未知错误
End
    End
GO
==================================================================
存储过程三：编辑分类
CREATE PROCEDURE sp_Column_Update
(
@Column_ID int,
@Parent_ID int,
@Column_Name nvarchar(50),
@Column_Intro nvarchar(1000)
)
AS
Declare @Err As int
Set @Err=0

Begin Tran

--获取修改前的：Parent_ID,Column_Depth,Column_Order
Declare @oParent_ID As int
Declare @oColumn_Depth As int
Declare @oColumn_Order As int
Declare @oColumn_Path As nvarchar(1000)

Select @oParent_ID = Parent_ID, @oColumn_Depth = Column_Depth,@oColumn_Order = Column_Order, @oColumn_Path = Column_Path  From Tb_Column Where Column_ID = @Column_ID
IF @oParent_ID Is Null
    Begin
    Set @Err = 1
    Goto theEnd
    End

--如果父ID没有改变，则直接修改栏目名和栏目简介
IF @oParent_ID = @Parent_ID
    Begin
    Update Tb_Column Set Column_Name = @Column_Name,Column_Intro = @Column_Intro Where Column_ID = @Column_ID
    IF @@Error <> 0
    Set @Err = 2
    Goto theEnd
    End

Declare @nColumn_Path As nvarchar(1000)
Declare @nColumn_Depth As int
Declare @nColumn_Order As int

--获取当前节点作为父节点所包含的节点数[包括自身] 注：如果返回 “1” 说明是单节点
Declare @theCount As int
Select @theCount = Count(Column_ID) From Tb_Column Where Column_ID=@Column_ID Or Column_Path like ''+@oColumn_Path+'|%'
IF @theCount Is Null
Begin
    Set @Err = 3
    Goto theEnd
End

IF @Parent_ID=0 --如果是设置为顶级节点，将节点设置为最后一个顶级节点
Begin
--Print '设置为顶级栏目'
Set @nColumn_Path = Ltrim(Str(@Column_ID))
Set @nColumn_Depth =1

Select @nColumn_Order = Max(Column_Order) From Tb_Column
IF @nColumn_Order Is NULL
                  Begin
     Set @Err = 4
     Goto theEnd
     End

Set @nColumn_Order = @nColumn_Order - @theCount + 1

--更新三部分 1 节点本身 2 所有子节点 2 本树更改之前的后面记录的顺序
--Print '更新本栏目之前位置后面的所有栏目[不包括本栏目下的子栏目]的：Column_Order'
Update Tb_Column Set Column_Order = Column_Order-@theCount Where (Column_Order >@oColumn_Order) And (Column_Path Not like ''+@oColumn_Path+'|%')
IF @@Error <> 0
    Begin
    Set @Err = 7
    Goto theEnd
    End

--Print '更新本栏目的：Parent_ID,Column_Path,Column_Depth,Column_Order,Column_Name,Column_Intro'
Print 'Order : '+Ltrim(Str(@nColumn_Order))
Update Tb_Column Set Parent_ID=@Parent_ID,Column_Path = @nColumn_Path,Column_Depth = @nColumn_Depth,Column_Order = @nColumn_Order, Column_Name = @Column_Name,Column_Intro = @Column_Intro Where Column_ID = @Column_ID
IF @@Error <> 0
    Begin
    Set @Err = 5
    Goto theEnd
    End

--Print '更新本栏目下的所有子栏目的：Column_Path,Column_Depth,Column_Order'
             Update Tb_Column Set Column_Path = Replace(Column_Path,@oColumn_Path,@nColumn_Path),Column_Depth = Column_Depth + (@nColumn_Depth-@oColumn_Depth),Column_Order = Column_Order+( @nColumn_Order-@oColumn_Order) Where Column_Path like ''+@oColumn_Path+'|%'
IF @@Error <> 0
    Begin
    Set @Err = 6
    Goto theEnd
    End

End
Else
Begin
--获取未来父节点的相关信息,并设置本节点的相关值
Select @nColumn_Depth = Column_Depth,@nColumn_Path = Column_Path From Tb_Column Where Column_ID = @Parent_ID
IF @nColumn_Depth Is  NULL Or @nColumn_Path Is Null
      Begin
      Set @Err = 8
      Goto theEnd
      End
Set @nColumn_Depth = @nColumn_Depth +1
Select @nColumn_Order =Max(Column_Order) From Tb_Column Where Column_ID = @Parent_ID Or  Column_Path like ''+@nColumn_Path+'|%'
IF @nColumn_Order Is  NULL
      Begin
      Set @Err = 9
      Goto theEnd
      End

Set @nColumn_Path = @nColumn_Path +'|'+ Ltrim(Str(@Column_ID))

IF @nColumn_Order = @oColumn_Order+1 --如果新的父节点是原来位置上端最近一个兄弟,则所有节点的顺序都不改变
                    Begin
Update Tb_Column Set Parent_ID=@Parent_ID,Column_Path = @nColumn_Path,Column_Depth = @nColumn_Depth, Column_Name = @Column_Name,Column_Intro = @Column_Intro Where Column_ID = @Column_ID
IF @@Error <> 0
    Begin
    Set @Err = 10
    Goto theEnd
    End
       End

Set  @nColumn_Order = @nColumn_Order + 1

--更新三部分 1 本树更改之前的后面（或前面）记录的顺序 1 节点本身  3 所有子节点
--分为向上移或象下移
--Print '更新本栏目之前位置后面的所有栏目[或者本栏目之后位置]  [不包括本栏目下的子栏目]的：Column_Order'
IF @nColumn_Order < @oColumn_Order
Begin
Update Tb_Column Set Column_Order = Column_Order+@theCount Where Column_Order<@oColumn_Order  And Column_Order >=@nColumn_Order And (Column_Path Not like ''+@oColumn_Path+'|%') And Column_ID<>@Column_ID
IF @@Error <> 0
        Begin
        Set @Err = 12
        Goto theEnd
        End
End
Else
Begin
Update Tb_Column Set Column_Order = Column_Order-@theCount Where Column_Order >@oColumn_Order And Column_Order<@nColumn_Order  And (Column_Path Not like ''+@oColumn_Path+'|%') And Column_ID<>@Column_ID
IF @@Error <> 0
        Begin
        Set @Err = 13
        Goto theEnd
        End
End

--Print '更新本栏目的：Parent_ID,Column_Path,Column_Depth,Column_Order,Column_Name,Column_Intro'
Print 'Order : '+Ltrim(Str(@nColumn_Order))
IF @nColumn_Order > @oColumn_Order
Set @nColumn_Order = @nColumn_Order - @theCount
Update Tb_Column Set Parent_ID=@Parent_ID,Column_Path = @nColumn_Path,Column_Depth = @nColumn_Depth,Column_Order = @nColumn_Order, Column_Name = @Column_Name,Column_Intro = @Column_Intro Where Column_ID = @Column_ID
IF @@Error <> 0
    Begin
    Set @Err = 10
    Goto theEnd
    End

--Print '更新本栏目下的所有子栏目的：Column_Paht,Column_Depth,Column_Order'
             Update Tb_Column Set Column_Path = Replace(Column_Path,@oColumn_Path,@nColumn_Path),Column_Depth = Column_Depth + (@nColumn_Depth-@oColumn_Depth),Column_Order = Column_Order+(@nColumn_Order-@oColumn_Order) Where Column_Path like ''+@oColumn_Path+'|%'
IF @@Error <> 0
    Begin
    Set @Err = 11
    Goto theEnd
    End
End

theEnd:
IF @Err<>0 --如果有错误则返回错误号
   Begin
   Rollback Tran
   Return @Err
   End
Else     --如果没有错误就返回0
   Begin
   Commit Tran
   Return 0
   End
GO
===========================================================================
存储过程四：显示分类（只是一条select语句）
分类列表：
CREATE PROCEDURE sp_Column_List
 AS
SELECT Column_ID, Column_Name, Parent_ID, Column_Path, Column_Depth,
      Column_Order, Column_Intro
FROM Tb_Column
ORDER BY Column_Order
GO

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这里有一个在ASP.NET下使用的例子，放在朋友一个论坛上：
http://www.mzline.com/bbs/dispbbs.asp?boardID=67&ID=5044&replyID=25788&star=1&skin=0#25788