Shulou(Shulou.com)06/01 Report--

Problem description: use scn number to recover mistakenly deleted data

1. Query the SCN value flashed by the system and the SCN value of the current log. Because mine is a test and the table created is in the back, so the SCN value is greater than the following two SCN values, so it is of no use for me to recover the data. If the data I created is before the following two SCN values, that is, less than the SCN values at these two time points, I can use these two scn to recover the data, but the test table I created in the next experiment is later. I can't do it.

SQL > select dbms_flashback.get_system_change_number from dual

SQL > select current_scn from v$database

two。 Create test data

SQL > create table aa (id int,name varchar2 (10), adress varchar2 (10))

SQL > insert into aa 2 values (111 mr.stevender mr.beijing`)

SQL > commit

3. At this time, it is equivalent to the data has been created, and the scn number after that should be known, because the above two scn numbers do not record the information of this table is of no use to me. If I query the current_scn number now, I will not bother to test here. The documentation is for reference.

SQL > select dbms_flashback.get_system_change_number from dual

This scn value can be used to recover data.

4. Delete the data simulation scenario, and then the data cannot be queried.

SQL > delete from aa;1 row deleted.SQL > commit;Commit complete.

5. Recover data

SQL > select * from aa as of scn 1116916

The previous data of this scn value can be queried and can be used to recover.

SQL > insert into sys.aa select * from sys.aa as of scn 1116916

Restore it now.

Summary

The above is the delete mistakenly deleted data introduced by the editor to you using the SCN number to restore, I hope it will be helpful to you, if you have any questions, please leave me a message, the editor will reply to you in time. Thank you very much for your support to the website!

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