整体undo使用情况查看

– 整体undo使用情况
select b.tablespace_name,
nvl(used_undo, 0) “USED_UNDO(M)”,
total_undo “Total_undo(M)”,
trunc(nvl(used_undo, 0) / total_undo * 100, 2) used_PCT
from (select nvl(sum(bytes / 1024 / 1024), 0) used_undo, tablespace_name
from dba_undo_extents
where status in (‘ACTIVE’, ‘UNEXPIRED’)
and tablespace_name in
(select value from v$parameter where name = 'undo_tablespace') group by tablespace_name) a, (select tablespace_name, sum(bytes / 1024 / 1024) total_undo from dba_data_files where tablespace_name in (select value from v$parameter where name = ‘undo_tablespace’)
group by tablespace_name) b
where a.tablespace_name(+) = b.tablespace_name;