Reporting Services :: TFS Ssrs Report For WorkItemType Drill Down Report

I need to create a SSRS report using the Warehouse tfs_warehouse DB Report need to be drill down on WorkItemType Parents and child values. So, If we click on Product Back Log Item will get all the tasks inside it and so on....

------->Product BackLog items
                          ----------> Bugs Or Tasks
                                                -----------> Tasks

I have done research and found out how to do it in OLAP cube ..but still can't figure out the TSQL query to be used.Found one of the query on forum:

SELECT * FROM DimWorkItem DWI
INNER JOIN FactWorkItemLinkHistory FWILH ON DWI.System_Id = FWILH.TargetWorkItemID
WHERE FWILH.WorkItemLinkTypeSK IN (SELECT DWILT.WorkItemLinkTypeSK FROM DimWorkItemLinkType DWILT WHERE DWILT.LinkName = N'Child')
AND DWI.System_WorkItemType = N'Task'
AND DWI.System_Rev = (SELECT MAX(DWI1.System_Rev) FROM DimWorkItem DWI1 WHERE DWI1.System_Id = DWI.System_Id)
AND FWILH.SourceWorkItemID IN (SELECT DWI2.System_Id FROM DimWorkItem DWI2 WHERE DWI2.System_WorkItemType = N'Bug');