1. Oracle 12R2 Database Flashback Technologies
Hariprasath Rajaram

2. Today’s Agenda

3. History of Oracle Flashback Technologies

4. Flashback Technologies Transformation Since V9
Flashback Version Query
Flashback Transaction Query
Flashback Table
Flashback Drop
Flashback Database
Flashback Query using
AS OF scn/timestamp
Session Level Flashback using
dbms_flashback
Statement Level Flashback using
AS OF clause
Flashback Transaction
Flashback Data Archive (Total Recall)
Flashback Standby Database
Multitenant : Flashback Pluggable Database (PDB)
Temporal Validity

5. Flashback Architecture Overview

6. Flashback Technologies Features
Flashback Query
Flashback Table
Flashback Drop
Flashback Versions Query
Flashback Transaction Query
Flashback Query Functions
Flashback Database
Flashback Data Archive
Flashback Pluggable Database (PDB)
Temporal Validity

7. Flashback Advanced use cases Flashback technology is integrated into Oracle Recovery Manager (RMAN) and Oracle Data Guard. So, apart from the basic use cases mentioned above, the following use cases are addressed using Oracle Flashback. Block Media recovery by RMAN - to perform block level recovery Snapshot Standby - where the standby is temporarily converted to a read/write environment for testing, backup, or migration purposes Re-instate old primary in a Data Guard environment – this avoids the need to restore an old backup and perform a recovery to make it a new standby. Guaranteed Restore Points - to bring back the entire database to an older point-in-time in a guaranteed way.

8. Flashback Architecture Overview
Type
Name
Purpose
Example Scenario
Investigation/
Correction
Flashback
Query
To query a table for a value at one previous point in time
verify the value alter batch update Replace the latest value of a column will a value as of 10AM
Investigation
Flashback Version
To query the changes that occurred in a table UNDO between two points in time
Monitor stock inventory quantity changes during the
past day Obtain the transaction
that changed the value
Transaction Query
To query the details of the transaction
To determine who initiated
the transaction and the values affected

9. Flashback Architecture Overview
Type
Name
Purpose
Example Scenario
Correction
Flashback Table
To rewind the table content
to a point in time
A few rogue update statements incorrectly updated multiple rows in the table Those updates need to be reversed
Flashback Drop
Undelete a dropped object
User accidentally dropped a table that needs to be restored
Flashback Transaction
Reverse a transaction
To reverse a transaction that
updated a few tables
CDP
Flashback Database
Rewind the entire database
to a previous point in time
User truncated a few important tables that need to be restored