Solution : https://service.sap.com/sap/support/notes/26312 (SAP Service marketplace login required)
Key words : 
sqldba lmode=ysqldba > connect internalsqldba > alter database backup controlfile, sqldba lmode=ysqldba > connect internalsqldba > recover database [, file $oracle_home/saptrace/usertrace/ora_<nnnnn>, ssqldba > alter database open [resetlogs], cd saptrace/usertracesqldba > ora_<nnnnn>, alter database create datafile, $datafile controlfile restore recovery, ignore empty file names, sqldba > exitto avoid, complete offline backup
Related Notes : 
       
| 21762 | |
| 4164 | Incomplete Recovery ("...RECOVER UNTIL... "). | 
| 4161 | Complete recovery |