oracle 查询占用undo资源的SQL

--查询占用undo资源的SQL
set pagesize 999 linesize 120
col machine for a16
col program for a20
col status for a10
col sql_id for a16
col sql_text for a20
select distinct s.machine,s.program,s.sid,round(t.used_ublk*8/1024,2) undo_MB,used_urec undo_records,s.status,l.sql_text
from v$transaction t,gv$session s,v$sqlstats l
where t.ses_addr=s.saddr
and s.sql_id=l.sql_id(+)order by undo_MB;

---查询回滚需要多久
select usn, state, undoblockstotal "Total", undoblocksdone "Done",
undoblockstotal-undoblocksdone "ToDo",
decode(cputime,0,'unknown',sysdate+(((undoblockstotal-
undoblocksdone) / (undoblocksdone / cputime)) / 86400))
"Estimated time to complete"
from v$fast_start_transactions;