Flashback

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Flashback is an Oracle database facility to quickly move an entire database or a table back to a prior state for recovery purposes. It can also be used to allow users to view data in a database "as it was", at a specified point in the past, even though committed transactions have since been applied.

History[edit]

Flashback was first introduced with Oracle 9i with Oracle's Flashback Query feature.

Oracle 10g added the following features:

Oracle 11g added Flashback Transaction and Total Recall (or Flashback Data Archive).

Enable database flashback[edit]

shutdown immediate;
startup mount;
alter database archivelog;
alter database flashback on;
alter database open;
SELECT flashback_on, log_mode FROM v$database;

DBMS_FLASHBACK[edit]

Example:

execute dbms_flashback.enable_at_time( -
  TO_TIMESTAMP('22-OCT-2007 22:00:00','DD-MON-YYYY HH24:MI:SS'));

Flashback DROP TABLE[edit]

To flashback (undrop) a table in the recycle bin:

FLASHBACK TABLE emp TO BEFORE DROP;
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