
Here are the steps you need to follow:
Check the box Import updates to existing data records in your clearquest database
Specify the filename
There is frame called importing record updates....
Select the cq field in which you imported the old_id(usually we name it old_id)
On the mapping page map the old_id to the id in your text file.
Hope this helps. Back up your databases before you try any of the steps.
Deepa