I recently executed an Oracle DB-Upgrade on Aix from Oracle 10.2.0.4 to 126.96.36.199.
We already did this more than 50 times and sometimes there are new situations you never had before. In this case the problem was with the dbua hanging at the beginning of the upgrade phase. There is the screen with the wheels and they keep running and running and i thought when will it finish (it usually takes only a few seconds). So after some analysis i found a metalink note regarding problems with an sql (v$rman_backup_job_details – don´t ask me why in this system).
I did the following, first i canceled the dbua. After that you execute the following steps:
1.) exec dbms_stats.DELETE_TABLE_STATS(‘SYS’,’X$KCCRSR’);
2.) alter system flush shared_pool; (or restart the database, should be possible if you are going to upgrade the database 😉
After executing steps mentioned above the sql regarding v$rman_backup_job_details will perform normal.
if you are not sure if you have this problem look in the trace.log or sqls.log under /oracle/cfgtoollogs/dbua/logs
maybe a search in oracles metalink may help further, i recommend looking in note [1314788.1]