Errors in file /u01/app/oracle/admin/XXXXX/bdump/xxxxxx_j000_8892588.trc:
ORA-12012: error on auto execute of job 1
ORA-00001: unique constraint (PERFSTAT.STATS$UNDOSTAT_PK) violated
ORA-06512: at "PERFSTAT.STATSPACK", line 2257
ORA-06512: at "PERFSTAT.STATSPACK", line 91
ORA-06512: at line 1

ALTER TABLE PERFSTAT.STATS$UNDOSTAT MODIFY CONSTRAINT STATS$UNDOSTAT_PK DISABLE NOVALIDATE;

SQL> select CONSTRAINT_NAME,TABLE_NAME,COLUMN_NAME, POSITION from dba_cons_columns where CONSTRAINT_NAME='STATS$UNDOSTAT_PK';

CONSTRAINT_NAME                TABLE_NAME                     COLUMN_NAME            POSITION
------------------------------ ------------------------------ -------------------- ----------
STATS$UNDOSTAT_PK              STATS$UNDOSTAT                 BEGIN_TIME                    1
STATS$UNDOSTAT_PK              STATS$UNDOSTAT                 END_TIME                      2
STATS$UNDOSTAT_PK              STATS$UNDOSTAT                 DBID                          3
STATS$UNDOSTAT_PK              STATS$UNDOSTAT                 INSTANCE_NUMBER               4

SQL>
-- Create un-unique index
CREATE INDEX PERFSTAT.STATS$UNDOSTAT_PK ON STATS$UNDOSTAT(BEGIN_TIME,END_TIME,DBID,INSTANCE_NUMBER);

----
有说这是9i的bug 2784796， 在cursor_sharing设置为similar或者force之后，可能触发此Bug。

但是此9i库的参数
SQL> show parameter cursor_sharing

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
cursor_sharing                       string      EXACT

不知何因。