FlashBack Query Posted by MOHAMMED ABDUL HAMEED on 8:00 AM

FlashBack Query :

It is used to retrive the data in past , point in time at Query Level.

SQL> show user;
USER is "HAMEED"

SQL> select * from tab;

TNAME                          TABTYPE  CLUSTERID
------------------------------ ------- ----------
INFO                           TABLE

SQL> set time on

20:57:11 SQL> select * from info;

ID      NAME
------  ----------
1            A

2           B

3           C


20:57:19 SQL> select sysdate from dual;

SYSDATE
---------
31-DEC-16

21:01:22 SQL> update info set name='AAA' where id='1';

1 row updated.

21:01:49 SQL> commit;

Commit complete.

21:03:23 SQL> select * from info;

ID      NAME
-----------------------
1        AAA

2          B

3          C

21:03:34 SQL> select * from info as of timestamp to_timestamp('31-DEC-16 21:01:22', 'dd-mon-rr hh24:mi:ss') where id=1;

ID     NAME
-------------------
1          A

21:04:05 SQL> update info set name=(select name from info as of timestamp to_timestamp ('31-DEC-16 21:01:22', 'dd-mon-rr hh24:mi:ss') where id=1) where id=1; 


1 row updated.

21:05:15 SQL> select * from info;

ID      NAME
-----------------------
1          A

2          B

3          C

21:16:53 SQL> commit;

Commit complete.