Solution : https://service.sap.com/sap/support/notes/1397192 (SAP Service marketplace login required)
Key words : 
terms migration partitioning key distribution key write-optimized datastore reason, prerequisites programm error solution sap netweaver bi 7, write-optimized datastore objects, primary key index ~0, datastore object tables, sap netweaver bi 7, sap netweaver bw 7, sap nw bi7, unique secondary indexes, sapbinews nw bi 7
Related Notes : 
       
| 1407600 | SAPBWNews NW BW 7.02 ABAP SP03 | 
| 1407599 | Preliminary Version SAPBWNews NW BW 7.20 ABAP SP03 | 
| 1407598 | SAPBWNews NW BW 7.0 ABAP SP 24 | 
| 1369294 | SAPBINews NW7.01 BW ABAP Support Package 07 | 
| 1260071 | SAPBINews NW 7.10 BI ABAP Support Package 08 |