以公司的網站欄目表爲例，表結構（表名：Subject）如下：
|
字段名稱
|
字段類型
|
字段長度
|
|
id
|
int
|
4
|
|
NAME
|
varchar
|
200
|
|
PARENTID
|
int
|
4
|
|
CODE
|
varchar
|
100
|
在數據庫中創建一個自定義函數：
CREATE FUNCTION dbo.GetSubtreeInfo
( @manager_id AS char(5)
)
RETURNS @treeinfo table
( [id] [int] NOT NULL ,
[name] [varchar] (100) NOT NULL,
[parentid] [int] NOT NULL,
[code] [varchar] (100) NULL,
[levels] [int] NOT NULL
) AS
BEGIN
DECLARE @level AS int
SELECT @level = 0
INSERT INTO @treeinfo
SELECT [id], [name], [parentid], [code], @level
FROM [subject]
WHERE [id] = @manager_id
WHILE @@ROWCOUNT > 0
BEGIN
SET @level = @level + 1
INSERT INTO @treeinfo
SELECT E.[id], E.[name], E.[parentid], E.[code], @level
FROM [subject] AS E JOIN @treeinfo AS T
ON E.[parentid] = T.[id] AND T.[levels] = @level - 1
END
RETURN
END
說明：其中的levels是樹狀結構的級數
使用方法：select SPACE(levels*3)+name ,* from GetSubtreeInfo(973) 其中973可以修改爲你要開始查詢的起始節點