Total Blocks Examined : 1
Total Blocks Processed (Data) : 1
Total Blocks Failing (Data) : 0
Total Blocks Processed (Index): 0
Total Blocks Failing (Index): 0
Total Blocks Empty : 0
Total Blocks Marked Corrupt : 0
Total Blocks Influx : 0
Message 531 not found; product=RDBMS; facility=BBED
刷新缓存，重新查看视图：
SYS@orcl11g>alter system flush buffer_cache;
System altered.
SYS@orcl11g>select segment_name,tablespace_name,status from dba_rollback_segs;
SEGMENT_NAME TABLESPACE_NAME STATUS
------------------------------ -------------------- ------------------------------------------------------------
SYSTEM SYSTEM ONLINE
_SYSSMU10_3550978943$ UNDOTBS1 OFFLINE
_SYSSMU9_1424341975$ UNDOTBS1 OFFLINE
_SYSSMU8_2012382730$ UNDOTBS1 OFFLINE
_SYSSMU7_3286610060$ UNDOTBS1 OFFLINE
_SYSSMU6_2443381498$ UNDOTBS1 OFFLINE
_SYSSMU5_1527469038$ UNDOTBS1 OFFLINE
_SYSSMU4_1152005954$ UNDOTBS1 OFFLINE
_SYSSMU3_2097677531$ UNDOTBS1 OFFLINE
_SYSSMU2_2232571081$ UNDOTBS1 OFFLINE
_SYSSMU1_3780397527$ UNDOTBS1 OFFLINE
_SYSSMU20_3705739785$ UNDOTBS02 ONLINE
_SYSSMU19_3920348761$ UNDOTBS02 ONLINE
_SYSSMU18_2539622763$ UNDOTBS02 ONLINE
_SYSSMU17_178842559$ UNDOTBS02 ONLINE
_SYSSMU16_3035903491$ UNDOTBS02 ONLINE
_SYSSMU15_444141832$ UNDOTBS02 ONLINE
_SYSSMU14_3021863913$ UNDOTBS02 ONLINE
_SYSSMU13_3717211136$ UNDOTBS02 ONLINE
_SYSSMU12_3182721254$ UNDOTBS02 ONLINE
_SYSSMU11_3909920883$ UNDOTBS02 ONLINE
SYS@orcl11g>select name,status$ from undo$;
NAME STATUS$
------------------------------------------------------------ ----------
SYSTEM 3
_SYSSMU1_3780397527$ 2
_SYSSMU2_2232571081$ 2
_SYSSMU3_2097677531$ 2
_SYSSMU4_1152005954$ 2
_SYSSMU5_1527469038$ 2
_SYSSMU6_2443381498$ 2
_SYSSMU7_3286610060$ 2
_SYSSMU8_2012382730$ 2
_SYSSMU9_1424341975$ 2
_SYSSMU10_3550978943$ 1
_SYSSMU11_3909920883$ 3
_SYSSMU12_3182721254$ 3
_SYSSMU13_3717211136$ 3
_SYSSMU14_3021863913$ 3
_SYSSMU15_444141832$ 3
_SYSSMU16_3035903491$ 3
_SYSSMU17_178842559$ 3
_SYSSMU18_2539622763$ 3
_SYSSMU19_3920348761$ 3
_SYSSMU20_3705739785$ 3