SAP Netweaver Business Intelligence BI / BW

Symptom
How to develop燼 date/time function (objects like " creation date since 6 months", "creation date since 3 months")爐o be used at the燚ata Federator Universe爈evel?e.g.:爐icket_creation_date >= today -? months (ticket open in the 3 last months)
Reproducing the Issue
Build a DF Universe in Business Objects Universe Designer,爓hich has燼s source a SAP BW system (currently the only type of DF Universe)
Create a new object at the Univers level,燼ccording to the requirements described above. This object will be used later in Webi/Deski reporting tools.Data Federator (DF): Any versionSAP BW 7.01 SP3 (Oracle DB)
Resolution
Example of a query that can be ran under DF Administrator for testing purpose:
select curDate(), toDate(timestampadd?(’SQL_TSI_MONTH’, -3, toTimeStamp(curDate()))) from /leselect/system/dual?
This query is using the dual test table, just to exemplify the use of DF internal functions. Since the DF Universe will accept only functions that DF knows how to interpret, a new object needs to be created under the DF Universe, using the above example.
Note: The Oracle DB under which our source system SAP BW runs is not important and such task can be achieved with DF internal functions only.