A schema owner truncated a table in error and must recover the data.
Which Oracle Flashback feature could be used to recover the data?
A schema owner truncated a table in error and must recover the data.
Which Oracle Flashback feature could be used to recover the data?
The correct Oracle Flashback feature to recover a table that has been truncated is FLASHBACK TABLE. This feature allows recovering the table to a point in time or SCN before the truncation occurred.
C correct
E, tested in practice
correct : E Backup and Recovery Workshop - typical scenario for Flashback Database is truncate table. You may use FBDA but in different way (not flashing back): insert into t1_recovered select * from t1 as of timestamp sysdate – 1/24;
It's E. Even with FLASHBACK DATA ARCHIVE, truncation of a table is possible, but will be a slow process.A retention time has to be specified. Refer to page 799 of the 12c All-in-one-exam-guide
It's E. Even with FLASHBACK DATA ARCHIVE, truncation of a table is possible, but will be a slow process.A retention time has to be specified. Refer to page 799 of the 12c All-in-one-exam-guide
It's E. Even with FLASHBACK DATA ARCHIVE, truncation of a table is possible, but will be a slow process.A retention time has to be specified. Refer to page 799 of the 12c All-in-one-exam-guide
Correct answer: E
I think E is wrong because it will flashback whole database, we just need to flashback a table
It is not possible to do a FlashbackTable to retrieve from Drop Table. Backup and Recovery User's Guide 19c, 18.2.1 Prerequisites for Flashback Table: .... For an object to be eligible to be flashed back, the following prerequisites must be met: .... The structure of the table must not have been changed between the current time and the target flashback time. The following Data Definition Language (DDL) operations change the structure of a table: upgrading, moving, or truncating a table; adding a constraint to a table, adding a table to a cluster; modifying or dropping a column; adding, dropping, merging, splitting, coalescing, or truncating a partition or subpartition (except adding a range partition).
Flashback Data Archive supports only these DDL statements: ... TRUNCATE TABLE statement https://docs.oracle.com/database/121/ADFNS/adfns_flashback.htm#ADFNS640
Without Flashback data archive (default configuration): SQL> insert into t1 values (1); 1 row created. SQL> commit; Commit complete. SQL> select current_scn from v$database; CURRENT_SCN ----------- 1754160 SQL> truncate table t1; Table truncated. SQL> flashback table t1 to SCN 1754160; flashback table t1 to SCN 1754160 * ERROR at line 1: ORA-01466: unable to read data - table definition has changed And the same error occurs after creating flashback data archive: SQL> CREATE FLASHBACK ARCHIVE DEFAULT mytest TABLESPACE users Quota 1M Retention 1 Day; Flashback archive created. and modifying t1 table to use it: SQL> alter table t1 flashback archive; Table altered.
FLASHBACK DATA ARCHIVE tested https://www.oracle.com/ocom/groups/public/@otn/documents/webcontent/4421812.pdf SELECT ... AS OF TIMESTAMP... SELECT ... VERSIONS BETWEEN TIMESTAMP and TIMESTAM SELECT * FROM t1 VERSIONS BETWEEN SCN 14759823 AND 14761165 SELECT * FROM t1 AS OF SCN 14759823; truncate SELECT * FROM t1 AS OF SCN 14761249; SELECT current_scn, TO_CHAR(SYSTIMESTAMP, 'YYYY-MM-DD HH24:MI:SS') FROM v$database;
Although Flashback Data Archive could flashback a truncated table, it can only recover until last flashback archive creation time but not point-in-time before the error occurs. Thus, choose E if point-in-time recovery required.
I'm with RinD. Go with C Database Development Guide
C Or E, both with arguements!!!
c Ref: 19.9.6 DDL Statements on Tables Enabled for Flashback Data Archive Flashback Data Archive supports only these DDL statements: ALTER TABLE statement that does any of the following: Adds, drops, renames, or modifies a column Adds, drops, or renames a constraint Drops or truncates a partition or subpartition operation TRUNCATE TABLE statement RENAME statement that renames a table https://docs.oracle.com/en/database/oracle/oracle-database/12.2/adfns/flashback.html#GUID-D01864A9-C642-4EDF-9EB0-796020A26F2D:~:text=NO%20FLASHBACK%20ARCHIVE%3B-,19.9.6%20DDL%20Statements%20on%20Tables%20Enabled%20for%20Flashback%20Data%20Archive,-Flashback%20Data%20Archive
I think the correct answer is C because, FLASHBACK DATA ARCHIVE is the only flashback option that if it is enabled can flashback some DDLs as TRUNCATE (here the reference https://docs.oracle.com/en/database/oracle/oracle-database/19/adfns/flashback.html#GUID-D01864A9-C642-4EDF-9EB0-796020A26F2D) FLASHBACK TABLE can also flashback truncate ONLY IF RESTORE POINT for Table was created
C or E could be correct
C is correct
@ObserverPL, I think that question assume recover only data from truncated table, so "flashback database" recover data with possible damages in other place. Of course it works, but the "flashback archive" be able to do that without any damages. @Neil107 there are no condition of that we should do as quickly as possible.
Sorry guys!. It seems my post doesn't get posted. A retry seems to repeat my post.