Continuing my series on Oracle Database Flashback.
(My first post on this topic was a week ago).
I create a Restore Point :
Oracle has captured a Restore Point. Note that this is *not* a Guaranteed Restore Point. Although the default Flashback Retention Target is 24 hours, However, Oracle maintains Flashback Logs to *target* the ability to flashback to 24hours ago. If the FRA is insufficient to hold all the Flashback Logs created over 24hours, some Flashback Logs may be deleted.
At any time, I can query my Flashback-ability status.
I had enabled Flashback on 01-Feb and there has been no activity in this database since then. So, I currently do have Flashback Logs upto the time they were first created.
Therefore : It is not a hard-and-fast rule that you can Flashback to the Flashback Retention Target. You might be able to flashback further back in time in an inactive database. On the other hand, in a very active database, with inadequate FRA, you might NOT be able to Flashback to the Flashback Retention Target.
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(My first post on this topic was a week ago).
I create a Restore Point :
[oracle@localhost Hemant]$ sqlplus '/ as sysdba' SQL*Plus: Release 11.2.0.2.0 Production on Sun Feb 8 22:55:28 2015 Copyright (c) 1982, 2010, Oracle. All rights reserved. Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - Production With the Partitioning, OLAP, Data Mining and Real Application Testing options SYS>create restore point Feb08_15; Restore point created. SYS> SYS>show parameter db_flashback_retention_target NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ db_flashback_retention_target integer 1440 SYS>
Oracle has captured a Restore Point. Note that this is *not* a Guaranteed Restore Point. Although the default Flashback Retention Target is 24 hours, However, Oracle maintains Flashback Logs to *target* the ability to flashback to 24hours ago. If the FRA is insufficient to hold all the Flashback Logs created over 24hours, some Flashback Logs may be deleted.
At any time, I can query my Flashback-ability status.
SYS> SYS>select * from v$flashback_database_log; OLDEST_FLASHBACK_SCN OLDEST_FL RETENTION_TARGET FLASHBACK_SIZE ESTIMATED_FLASHBACK_SIZE -------------------- --------- ---------------- -------------- ------------------------ 14569609 01-FEB-15 1440 24576000 0 SYS>
I had enabled Flashback on 01-Feb and there has been no activity in this database since then. So, I currently do have Flashback Logs upto the time they were first created.
Therefore : It is not a hard-and-fast rule that you can Flashback to the Flashback Retention Target. You might be able to flashback further back in time in an inactive database. On the other hand, in a very active database, with inadequate FRA, you might NOT be able to Flashback to the Flashback Retention Target.
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