Question:
What is the
dba_flashback_archive view?
How can dba_flashback_view be used to monitor Oracle
flashback?
Answer: The dba_flashback_archive
view contains the columns flashback_archive_name,
flashback_archive#,
retention_in_days,
create_time,
last_purge_time and
status to help the DBA
administer the flashback feature of Oracle.
For more details see my notes on
using total
recall with flashback data archive.
Here is the query to show the
dba_flashback_archive
contents:
select
flashback_archive_name,
status
from
dba_flashback_archive;
The
dba_flashback_archive describes all flashback
archives in the database and the status column of
dba_flashback_archive indicates whether the flashback archive
is a default archive for the database.
All DBA's will
enable a flashback_data_archive area that can then be seen by
dba_flashback_archive.
Please note these limitations on using DDL with 11g
flashback data archive.
With a flashback data archive it is possible to view data as any
point in time since the flashback data archive was created.
However, attempting to view data as a timestamp before the data
archive is created causes the following
ORA-01466 flashback error:
ORA-01466: unable to read data -
table definition has changed
If you try to drop a flashback tablespace that is in-use you get
the ORA-55641 error:
SQL > alter flashback
flashback_archive_area_one archive remove tablespace
flashback_tablespace_one;
ORA-55641: Cannot drop
tablespace used by Flashback Data Archive
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