ORA-01548 after bounce the Database...

Question

Hi All,
User has run some job which occupied 50G in undo tablespace. Now job is finished and I want to reclaim that 50G from undo.
So I created another undo tbs of small size say 2G and switch to new undo tbs.. all segment is online with new undotbs but one segment having "partial available" status with old undotbs.
I bounce the DB also but still when going to delete older undotbs its throwing me this error:
drop tablespace undotbs2 including contents and datafiles
ERROR at line 1:
ORA-01548: active rollback segment '_SYSSMU23$' found, terminate dropping
tablespace
when I check how many extent with this "_SYSSMU23$" segment..it gives 384 rows with "ACTIVE" status.
select owner,segment_name,tablespace_name,status from dba_undo_extents where segment_name='_SYSSMU23$';
how can I reclaim my undo space ?
Any suggestion?
Thanks...

Answer 1

Hi Nagendra,
select tablespace_name,status,count(*) as HOW_MANY from dba_undo_extents group by tablespace_name,status
TABLESPACE_NAME STATUS HOW_MANY
UNDOTBS2 EXPIRED 1195
TESTUND EXPIRED 294
TESTUND UNEXPIRED 116
from the above query it shows UNDOTBS2 having expired extents but with one of the segment it showing "active" status as below:
SQL> select owner,segment_name,tablespace_name,status from dba_undo_extents where segment_name='_SYSSMU23$';
OWN SEGMENT_NAME TABLESPACE_NAME STATUS
SYS _SYSSMU23$                     UNDOTBS2                       ACTIVE       
SYS _SYSSMU23$                     UNDOTBS2                       ACTIVE       
SYS _SYSSMU23$                     UNDOTBS2                       ACTIVE