Solution : https://service.sap.com/sap/support/notes/1500756 (SAP Service marketplace login required)
Key words : 
symptom dump itab_duplicate_key occurs, solution sap netweaver bw 7, sap netweaver bw 7, langu   = sy-langu, objvers = rs_c_objvers-active, sap nw bw 7, function module rssm_process_get_odsname, 01 bw abap sp08, 30 bw abap sp01, sapbinews nw bi 7
Related Notes : 
       
| 1500078 | SAPBWNews NW BW 7.02 ABAP SP06 | 
| 1471463 | SAPBWNews NW BW 7.01 ABAP SP08 | 
| 1468668 | SAPBWNews NW7.0 BW ABAP Support Package 25 | 
| 1392433 | SAPBINews NW7.11 BW ABAP Support Package 05 |