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I see frequent questions regarding “How to Rollback database changes after commit” or “How to flashback my table to previous state”. One such questions was asked here http://stackoverflow.com/questions/27309730/how-to-rollback-my-db-changes-after-a-commit/27309814#27309814

Basically, there is nothing like a ROLLBACK after a COMMIT. However, you can do a FLASHBACK on the table in the following ways :-

There are two things,

1.Flashback by SCN

SELECT column_list
FROM table_name
AS OF SCN scn_number;

2.Flashback by TIMESTAMP

SELECT column_list
FROM table_name
AS OF TIMESTAMP TO_TIMESTAMP('the timestamp value');

To get current_scn and systimestamp, query :

SELECT current_scn, SYSTIMESTAMP
FROM v$database;

Let’s see an example :

To flashback the table to the old scn, use FLASHBACK TABLE..TO SCN clause.


SQL> DROP TABLE string_ex PURGE;
Table dropped.

SQL> CREATE TABLE string_ex (sl_ps_code VARCHAR2(20) );

Table created.

SQL> INSERT INTO string_ex (sl_ps_code) VALUES ('AR14ASM0002');

1 row created.

SQL> INSERT INTO string_ex (sl_ps_code) VALUES ('AR14SFT0018');

1 row created.

SQL> INSERT INTO string_ex (sl_ps_code) VALUES ('AR14SFT0019');

1 row created.

SQL> INSERT INTO string_ex (sl_ps_code) VALUES ('AR14SFT0062');

1 row created.

SQL> COMMIT;

Commit complete.

SQL> SELECT current_scn, SYSTIMESTAMP FROM v$database;

CURRENT_SCN SYSTIMESTAMP
-------------------- --------------------------------------------
13818123201277 29-OCT-14 03.02.17.419000 PM +05:30

SQL> SELECT current_scn, SYSTIMESTAMP FROM v$database;

CURRENT_SCN SYSTIMESTAMP
-------------------- --------------------------------------------
13818123201280 29-OCT-14 03.02.22.785000 PM +05:30

SQL> SELECT current_scn, SYSTIMESTAMP FROM v$database;

CURRENT_SCN SYSTIMESTAMP
-------------------- --------------------------------------------
13818123201282 29-OCT-14 03.02.26.781000 PM +05:30

SQL> SELECT * FROM string_ex;

SL_PS_CODE
---------------
AR14ASM0002
AR14SFT0018
AR14SFT0019
AR14SFT0062

SQL>

I have four rows in the table.

SQL> ALTER TABLE string_ex ENABLE ROW MOVEMENT;

Table altered.

SQL>

Row movement is required.


SQL> DELETE FROM string_ex WHERE ROWNUM =1;

1 row deleted.

SQL>
SQL> COMMIT;

Commit complete.

SQL>
SQL> SELECT * FROM string_ex;

SL_PS_CODE
---------------
AR14SFT0018
AR14SFT0019
AR14SFT0062

I deleted a row now and committed the changes.


SQL> FLASHBACK TABLE string_ex TO SCN 13818123201277;

Flashback complete.

Flashback is complete


SQL> SELECT * FROM string_ex;

SL_PS_CODE
---------------
AR14ASM0002
AR14SFT0018
AR14SFT0019
AR14SFT0062

SQL>

I now have my table to old state and the row is back

Hope it helps!