Many thanks to Amanjit and Colleen for their guidance.
In case there is a business need to have single approval for Manager & Role Owner where both happens to be the same person, below is the solution:
This can be achieved using Multiple DBLookups....in this case 4 DBLookups:
1. Get Request ID
2. Get Role ID
3. Get the Manager ID
4. Get the Role Approver ID
Following are the steps:
Step 1: Get Request ID
Request ID is in GRACREQ (Request Header) where REQNO = Request.ReqNo (select from context parameter) . This will be used as expression in Manager ID Table to get the Manager for this Request only and not any other request.
Step 2: Get Role ID
Request ID is in GRACROLE (Role) where Role_Name=Request.Role_Name (select from context parameter) . This will be used as expression in Role ID Table to get the Role for this Request only and not any other request.
Step 3: Get Manager ID
Now create DBLookup for Manager ID. Manager ID is in GRACREQOWNER Table with Req_ID=Get_REQ_ID (Request No from Step 1) and UserType="MAN". Put that ID in a variable lets say User ID.
Step 4: Get Role Approver ID
Role Approver ID is in GRACROLEAPPRVR Table where Role_ID=Get_Role_ID (Role ID from Step 2).We can put that in Approver Variable.
Step 5: Create Condition in Decision Table
Create simple condition that if DBLOOKUP-MGR=DBLOOKUP-ROW (Manager = Role Owner) then True otherwise False.
Hope this helps.
Best Regards.
Shahid.