查询UNDO使用情况

查看UNDO事务占用情况

SELECT s.username,
s.sid,
pr.PID,
s.OSUSER,
s.MACHINE,
s.PROGRAM,
rs.segment_id,
r.usn,
rs.segment_name,
r.rssize/1024/1024,
sq.sql_text
FROM v$transaction t, v$session s, v$rollstat r, dba_rollback_segs rs ,v$sql sq,v$process pr
WHERE s.saddr = t.ses_addr
AND t.xidusn = r.usn
AND rs.segment_id = t.xidusn
AND s.sql_address=sq.address
AND s.sql_hash_value = sq.hash_value
AND s.PADDR=pr.ADDR
ORDER BY t.used_ublk DESC

Undo整体的使用状况：

SELECT seg.tablespace_name "Tablespace Name",
ts.bytes / 1024 / 1024 "TS Size(MB)",
ue.status "UNDO Status",
count(*) "Used Extents",
round(sum(ue.bytes) / 1024 / 1024, 2) "Used Size(MB)",
round(sum(ue.bytes) / ts.bytes * 100, 2) "Used Rate(%)"
FROM dba_segments seg,
DBA_UNDO_EXTENTS ue,
(SELECT tablespace_name, sum(bytes) bytes
FROM dba_data_files
GROUP BY tablespace_name) ts
WHERE ue.segment_NAME = seg.segment_NAME
and seg.tablespace_name = ts.tablespace_name
GROUP BY seg.tablespace_name, ts.bytes, ue.status
ORDER BY seg.tablespace_name;