Roll back Update or delete data Through Flashback query - sql

Question

I have done some changes and commited but i want to roll back those changes through Flashback query.
Can you please help me how to do this?
I am using Oracle 11g Version.
From below tables i have deleted the data..Now i want to revert back those records..
Customer,
Address,
Employee,
Alignemnt
Many Thanks for your help.
Sunitha.

Answer 1

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$database;
Update Example as requested by OP.
To flashback the table to the old scn, use FLASHBACK TABLE..TO SCN clause.
SQL> DROP TABLE string_ex PURGE;
Table dropped.
SQL> CREATE TABLE string_ex (sl_ps_code VARCHAR2(20) );
Table created.
SQL> INSERT INTO string_ex (sl_ps_code) VALUES ('AR14ASM0002');
1 row created.
SQL> INSERT INTO string_ex (sl_ps_code) VALUES ('AR14SFT0018');
1 row created.
SQL> INSERT INTO string_ex (sl_ps_code) VALUES ('AR14SFT0019');
1 row created.
SQL> INSERT INTO string_ex (sl_ps_code) VALUES ('AR14SFT0062');
1 row created.
SQL> COMMIT;
Commit complete.
SQL> SELECT current_scn, SYSTIMESTAMP FROM v$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