180329 FLASHBACK DB 실습 1 (환경설정)

[oracle@localhost ORCL]$ cd flashback

[oracle@localhost flashback]$ ls

o1_mf_fcrysm57_.flb

[oracle@localhost flashback]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.1.0 Production on Thu Mar 29 14:39:24 2018

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production

With the Partitioning, Oracle Label Security, OLAP, Data Mining,

Oracle Database Vault and Real Application Testing options

SYS@orcl>show parameter db_recovery

NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

db_recovery_file_dest                string      /u01/app/oracle/flash_recovery

                                                 _area

db_recovery_file_dest_size           big integer 10G

SYS@orcl>show parameter db_flashback;

NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

db_flashback_retention_target        integer     1440 (1440분하루치) alter system set 으로 수정할 수 있다.

      ALTER SYSTEM SET db_flashback_retention_target = 2880 SCOPE=BOTH

SYS@orcl>select scn_to_timestamp(1863728) from dual;   < EM에서 Lowest SCN in the flashback data 번호를 가져와서 실행하면 

         되돌릴 수 있는 과거 시간을 보여준다.(시간을 scn으로 저장)

SCN_TO_TIMESTAMP(1863728)

---------------------------------------------------------------------------

29-MAR-18 02.35.43.000000000 PM

현재를 보려면

SYS@orcl>select current_scn from v$database;

CURRENT_SCN

-----------

    1864867

SYS@orcl>/

CURRENT_SCN ( 시간이 지날 수록 숫자가 올라간다 System Change Number인듯)

-----------

    1864871

설정 완료!