SQL> select * from dba_segments where segment_type='ROLLBACK';
OWNER SEGMENT_NAME PARTITION_NAME SEGMENT_TYPE TABLESPACE_NAME HEADER_FILE HEADER_BLOCK	     BYTES   BLOCKS  EXTENTS INITIAL_EXTENT NEXT_EXTENT MIN_EXTENTS MAXEXTENTS PCT_INCREASE FREELISTS FREELIST_GROUPS RELATIVE_FNO BUFFER_
----- ------------ -------------- ------------ --------------- ----------- ------------ ---------- --------  ------- -------------- ----------- ----------- ---------- ------------ --------- --------------- ------------ -------
  SYS       SYSTEM                    ROLLBACK          SYSTEM           1            2     102400      500       20          51200       51200           2        121            0         1               1            1 DEFAULT
  SYS          R01                    ROLLBACK             RBS           2           33	-8.773E+09 -4283384 -4283384       83886090     1048576           1      32765            0         1               1            2 DEFAULT
  SYS          R02                    ROLLBACK             RBS           2        16417	-8.772E+09 -4282944 -4282944       83886090     1048576           1      32765            0         1               1            2 DEFAULT
  SYS          R03                    ROLLBACK             RBS           2         8225	-8.772E+09 -4282944 -4282944       83886090     1048576           1      32765            0         1               1            2 DEFAULT
  SYS          R04                    ROLLBACK             RBS           2         4129	-8.772E+09 -4282944 -4282944       83886090     1048576           1      32765            0         1               1            2 DEFAULT
  SYS          R05                    ROLLBACK             RBS           2        20513	-8.772E+09 -4282944 -4282944       83886090     1048576           1      32765            0         1               1            2 DEFAULT
  SYS	    BIGRBS                    ROLLBACK             RBS           2        57337	-8.772E+09 -4282944 -4282944       83886090     1048576           1      32765            0         1               1            2 DEFAULT
SQL>