sql树形结构查询语句

执行sql语句

WITH COMMENT_CTE(ClassID,ClassParentID,ClassName) 
AS 
 (
	SELECT ClassID,ClassParentID,ClassName FROM HardwareClass
	WHERE ClassParentID='126' 
	UNION ALL 
	SELECT c.ClassID,c.ClassParentID,c.ClassName FROM HardwareClass AS c 
	INNER JOIN 		COMMENT_CTE AS ce 
	ON c.ClassParentID=ce.ClassID) 
SELECT * FROM COMMENT_CTE; 

结果如下：