Having problems with subworktask_subworkid

DeloitteAdmin_(Delete)_2707331

Hello,I have a main workflow which kicks off subworkflows.I need to list the details of the main workflow and the ID of the subworkflow in a report.I then want to pass the ID of the sub workflow into another report..The problem I am having is listing the subworkflow ID, when I try to list the subworktask_taskid, it displays all the tasks for that workflow..which then creates duplicate values etc etc...how to i list the subworktask_taskid once only?hope that makes sense..Thanks,Asha