Solution : https://service.sap.com/sap/support/notes/536223 (SAP Service marketplace login required)
Key words : 
restores previous system behavior, time-independent navigation attributes, unusually complex sql statements, 0b            import support package 26, 1c            import support package 18, 0b            import support package 04, suitable execution plan, sap db rsdrx_split_xy_fill_exec -2-, suitable access plan, database errors due
Related Notes : 
       
| 1416955 | DB6: Activation of an InfoObject never ends, or fails | 
| 765740 | DB6: Resolve aborts/timeouts during master data activation | 
| 739553 | Error when activating an InfoObject | 
| 697775 | DB6: Activating master data with navigation attributes | 
| 523196 | SAPBWNews BW 2.1C Support Package 18 | 
| 523133 | SAPBWNews BW 2.0B Support Package 26 | 
| 514907 | Processing complex queries (data mart, and so on) | 
| 493975 | SAPBWNews BW 3.0B Support Package 04 | 
| 458702 | SAPBWNews BW 3.0A Support Package 10 |