Oracle 19c Flashback Technology (6/7): Flashback Database/PDB

In Oracle Database 19c, Flashback Database allows you to rewind your database to a previous point in time — without restoring backups.

With the Multitenant architecture (CDB/PDB), Flashback can be performed:

• At CDB level
• At PDB level (independently)

This article explains configuration, and practical examples for Flashback Database on a PDB.

1. What is Flashback Database?

Flashback Database allows you to:

• Rewind the database to a past SCN or timestamp
• Recover from logical errors (accidental delete, update, drop, etc.)
• Avoid full restore + recovery

It works using:

• Flashback Logs (stored in FRA)
• UNDO
• Redo logs

2. Flashback in Multitenant (CDB/PDB)

In 19c:

Level	Supported	Notes
CDB	Yes	All PDBs are flashed back
Individual PDB	Yes	Since 12.2+
Single table	Use Flashback Table instead

Important: Flashback Database is different from Flashback Table.

3. Prerequisites

Step 1 – Enable ARCHIVELOG

SHUTDOWN IMMEDIATE;
STARTUP MOUNT;
ALTER DATABASE ARCHIVELOG;
ALTER DATABASE OPEN;

Step 2 – Configure FRA

ALTER SYSTEM SET DB_RECOVERY_FILE_DEST_SIZE = 20G;
ALTER SYSTEM SET DB_RECOVERY_FILE_DEST = '/u01/app/oracle/fast_recovery_area';

Step 3 – Enable Flashback at CDB Level (Not at PDB Level)

SHUTDOWN IMMEDIATE;
STARTUP MOUNT;
ALTER DATABASE FLASHBACK ON;
ALTER DATABASE OPEN;

Verify:

SELECT flashback_on FROM v$database;

Should return:

YES

4. How Far Back Can You Go?

Depends on:

• FRA size
• Flashback retention target

SHOW PARAMETER db_flashback_retention_target;

Default:

1440 minutes (24 hours)

Increase if needed:

ALTER SYSTEM SET db_flashback_retention_target = 2880;

5. Flashback PDB

sqlplus sys/oracle_4U@pdb as sysdba

Connected to:

Oracle Database 19c Enterprise Edition
Version 19.3.0.0.0

Step 1. – Close the PDB

Flashback requires the PDB to be closed.

SQL> ALTER PLUGGABLE DATABASE pdb CLOSE immediate;

Pluggable database altered.

Step 2 – Flashback PDB to Timestamp

We rewind to the timestamp captured before the update:

SQL> FLASHBACK PLUGGABLE DATABASE pdb 
     TO TIMESTAMP TO_TIMESTAMP('03/09/25 18:30:20','dd/mm/yy hh24:mi:ss');

Output:

Flashback complete.

Oracle restored the PDB to the exact moment before the update.

Step 3 – Open PDB with RESETLOGS

SQL> ALTER PLUGGABLE DATABASE pdb OPEN RESETLOGS;

Pluggable database altered.

RESETLOGS is mandatory after Flashback Database.

Step 4 – Verify Data Is Restored