递归查询计算文件夹大小

如何解决递归查询计算文件夹大小

我尝试在 sql Server 中执行以下场景：

     Root Folder (dataID - 001)
                 Folder A (dataid-123)
                       child folder 1 
                             doc1 (size-6 mbs)
                             doc2  (size- 10 mbs)   
                       child folder 2
                             doc3  (size - 1 mbs)
                             doc4  (size- 50 mbs)
                 Folder B (dataId- 456)
                       child folder 1 
                             doc1 (size-4 mbs)
                             doc2  (size- 8 mbs)    
                       child folder 2
                             doc3  (size - 8 mbs)
                             doc4  (size- 3 mbs)
                       child folder 3
                             doc5  (size - 3 mbs)
                             doc6  (size- 7 mbs)
                                   SubChild folder 1 for child folder 3
                                             doc 7 (size - 9 mbs)
                                                   SubSubChild Folder1 for SubChild folder1                          
                                                         doc 8 (size 5 mbs)

我试图获得的输出格式如下：

              Name       Count of Docs   Total Folder Size:
              FolderA        4               67Mbs
              FolderB        8               47Mbs

如果我提供根文件夹 ID，我所形成的查询只允许我获取所有文档的大小和数量：

              WITH n(DataID,Name,ParentID,SubType,versionnum) AS 

             (SELECT DataID,versionnum
              FROM DTreeCore
              WHERE DataID = 001
              UNION ALL
              SELECT nplus1.DataID,nplus1.Name,nplus1.ParentID,nplus1.SubType,nplus1.versionnum 
              FROM DTreeCore as nplus1,n
              WHERE n.DataID = nplus1.ParentID)

              SELECT COUNT(d3.docid) AS "Number of Docs",SUM(d3.datasize) /(1024 *1024) "Megabytes" 
              FROM
              n,dversdata d3 
              WHERE 
              n.dataid = d3.docid AND 
               n.versionnum = d3.version

请告诉我如何实现所需的输出。谢谢！