Oracle 11g Flashback examples

Environment: Oracle database 11.2.0.3.0 Enterprise Edition.

This is a quick overview (mostly for myself ;-)) of the flashback features that are available with Oracle 11g.

— query table data from specific point in time

SELECT * FROM matthiash
AS OF TIMESTAMP
TO_TIMESTAMP('2013-05-03 14:00:00', 'YYYY-MM-DD HH24:MI:SS');

— query table data from one hour ago

SELECT * FROM matthiash
AS OF TIMESTAMP
(SYSTIMESTAMP - INTERVAL '60' MINUTE);

— query all versions of one or more records

SELECT versions_startscn, versions_starttime,
versions_endscn, versions_endtime,
versions_xid, versions_operation,m_id
FROM matthiash
VERSIONS BETWEEN TIMESTAMP
TO_TIMESTAMP('2013-05-03 13:00:00', 'YYYY-MM-DD HH24:MI:SS')
AND TO_TIMESTAMP('2013-05-03 14:45:00', 'YYYY-MM-DD HH24:MI:SS')

— get the user name of the user who modified records

GRANT SELECT ANY TRANSACTION TO matthiash;

SELECT xid, logon_user
FROM flashback_transaction_query
WHERE xid IN (
SELECT versions_xid FROM matthiash VERSIONS BETWEEN TIMESTAMP
TO_TIMESTAMP('2013-05-03 13:00:00', 'YYYY-MM-DD HH24:MI:SS')
AND TO_TIMESTAMP('2013-05-03 14:45:00', 'YYYY-MM-DD HH24:MI:SS')
)
AND xid = HEXTORAW('08000800C6070000');

— flashback entire table to specific point in time

ALTER TABLE matthiash ENABLE ROW MOVEMENT

FLASHBACK TABLE matthiash
TO TIMESTAMP TO_TIMESTAMP('2013-05-03 13:00:00', 'YYYY-MM-DD HH24:MI:SS');

— creating restore point and flashback table to restore point

CREATE RESTORE POINT before_table_update;

SELECT NAME, SCN, TIME
FROM V$RESTORE_POINT;

UPDATE matthiash SET m_id=0;

FLASHBACK TABLE matthiash.matthiash
TO RESTORE POINT before_table_update;

— recover dropped table from recycle bin (note: does not work for all types of tables)

DROP TABLE matthiash;

SELECT * FROM recyclebin;

FLASHBACK TABLE matthiash TO BEFORE DROP;

FLASHBACK TABLE "BIN$29FWNr5ICjbgQ68BEqzYLw==$0" TO BEFORE DROP RENAME TO matthiash;

— recover entire database to restore point, SCN or point in time

CREATE RESTORE POINT before_table_drop GUARANTEE FLASHBACK DATABASE;

DROP TABLE matthiash PURGE;

SHUTDOWN IMMEDIATE;
STARTUP MOUNT;

FLASHBACK DATABASE TO RESTORE POINT BEFORE_TABLE_DROP;

FLASHBACK DATABASE TO SCN 46963;

FLASHBACK DATABASE TO TIME "TO_TIMESTAMP('2013-05-03 15:00:00', 'YYYY-MM-DD HH24:MI:SS')";

ALTER DATABASE OPEN RESETLOGS;

Matthias

9 thoughts on “Oracle 11g Flashback examples

  1. G’day Matthias. Curious as to why you used RMAN in the last example of flashback database.

    You can issue those flashback commands from within SQLPLUS if desired.

  2. It works well. But only works on big tables, if the undo tabespace is big enough. I only use it to correct data after wrong sql-statements ;) for better history i use an extra table for logging datachanges

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