Master note for Oracle Backup & Recovery

• Master Note For Oracle Flashback Technologies [1138253.1]
• Master Note For Oracle Backup And Recovery [1199803.1]
• Master Note For Oracle Recovery Manager (RMAN) [1116484.1]
• Master Note for Data Guard [1101938.1]
• Master Note for Export and Import [1264691.1]
• Master Note for Data Pump [1264715.1]
• Master Note for SQL*Loader [1264730.1]
• Master Note for LogMiner [1264738.1]

Find Top 5 Datafiles with highest I/O activity

col name format a40
set linesize 140
select * from (select name,phyrds, phywrts,readtim,writetimfrom v$filestat a, v$datafile b 
where a.file#=b.file#order by readtim desc) where rownum <6; 

Find Top Undo Consumers in Oracle

SELECT TO_CHAR(s.sid) || ',' || TO_CHAR(s.serial#) sid_serial, 
NVL(s.username, 'None') orauser, s.program, r.name undoseg, 
t.used_ublk * TO_NUMBER(x.value) / 1024 || 'K' "Undo" 
FROM sys.v_$rollname r, sys.v_$session s, sys.v_$transaction t, sys.v_$parameter x WHERE s.taddr = t.addr AND r.usn = t.xidusn(+) 
AND x.name = 'db_block_size';