1) Ok, there are no database level triggers.

SQL> startup
ORACLE instance started.

Total System Global Area 336560912 bytes
Fixed Size 742160 bytes
Variable Size 218103808 bytes
Database Buffers 117440512 bytes
Redo Buffers 274432 bytes
Database mounted.
ORA-00604: error occurred at recursive SQL level 1
ORA-00942: table or view does not exist

SQL> select trigger_name, trigger_type, triggering_event from dba_triggers where triggering_event = 'STARTUP';

no rows selected

2) There are no objects pinned in the SGA on startup.
3) And no there was no upgrade from 8.1.7 instance. The database is
9.2.0.3.0 - 64bit Production.