Where are BLOB Files stored when using redo log files.

I am using Archive Log Mode for my backups. I was wondering if Blob files get stored in the redo log files or if they are archived somewhere else?
Rob.

BLOB are just columns of some tables and are stored in related tablespace table by default in their own segments. Changes to BLOB columns are also stored in redo log more or less like any other column.
See an short example for default LOB storage in Re: CLOB Datatype [About Space allocation]
Edited by: P. Forstmann on 27 avr. 2011 07:20

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Hi,
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user12141893 wrote:
Does it mean:
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This is sort of correct. If the log file would be filled up , LGWR would switch over to the next log group and would initiate a Log Switch which would further trigger DBWR to start checkpointing the content protected by this log group to the data file. By the time this operation would be going on, the Log group's members would have the status of Active and once it would be complete, the status would be marked to Inactive which means that this log group and its members can be reused by LGWR.
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Roger25 wrote:
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Dropping Log Groups
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http://download.oracle.com/docs/cd/B10500_01/server.920/a96521/onlineredo.htm#7438
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Redo log files in case of NOARCHIVELOG Mode.

Question is related with the oracle architure..
database requires a minimum of two redo log files to guarantee that one is always available for writing while the other is being archived, this sounds perfect when DB is running in ARCHIVELOG mode but at the same time it also forces database to have 2 redo log files even when the DB is running in NOARCHIVELOG mode?
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I would look for reasons not answers on what redo log is and what information it holds etc..

pgoel wrote:
If you had only one file all further changes would have to stop until all changed data blocks had been written to disc. By insisting on a minimum of two log files Oracle can allow the log writer to fill the second log file as the database writer writes out the dirty blocks covered by changes desrcibed in the first log file.What about having a big size redo log file instead of two? Checkppoint being initiated when the redo log file is half filled
I mean, understand the logic, two is better, even best.. but still not getting convinced. I am just trying to think, can not Oracle work with 1 group with 1 big file..specailly when Noarch mode ? Having
Edited by: pgoel on Mar 12, 2011 7:27 PMNo, you still didn't understand and I am not sure how else we can say it. Okay, think about log groups as two buckets which are used to fill the redo content. The LGWR is filling one bucket at a time till it can't accept any more content. Once filled, rather than spilling the content out, it jumps over to the second bucket. Now, taking your statement of big sized redo, Pgoel, it doesn't matter how big sized bucket you bring in, eventually it will fill in. Its not possible that you wont be able to fill it , it just would take more longer than the normal timings. Thats all. So in any case , you need the second bucket. And I am not sure that why you are struck on the archivelog mode. I hope you do understand that its an optional mode. This means, this may or may not be there. If there, its a good thing that before doing the flush of the redo content, Oracle would be able to save the contents in the archived (think about the name, it's very meaning is to preserve, to archive) log file. If not, the redo content wuold be lost and there won't be any record of transactions leaving you to reenter the lost transactions. Its a meaningless point on which you are struck i.e. the archive or no-archivelog mode. Be it whatever, Oracle would still need minimum of the two log groups.
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I got a scenario in which my current redo log file is lost:
Do I need to:
1)Clear log file group
(or)
2)I should perform incomplete recovery.
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CANCEL
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Begin incomplete media recovery, recovering up through the log before the damaged log.
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Open the database using the RESETLOGS option:
ALTER DATABASE OPEN RESETLOGS;
My question is when the redo log file is current. What steps we should follow?
Best regards,
Rafi.
http://rafioracledba.blogspot.com/
2)If it is active then I can make use of below steps:

Rafi (Oracle DBA) wrote:
Hi Asif,
This link I have seen by refering to previous post.I just have a slight doubt in mind.
1)Do I need to make use of statement:
Alter database clear unarchived log file group#;
(or)
Only if your group is current(or you are not able to drop it) and is not archived then you should use above query.
We should perform incomplete recovery for this.If we have to perform incomplete recovery what are the steps I should follow?
I doubt you should be performing incomplete recovery for this.
Eg:Let us say my group 1 is dropped it has only one member and it is in active state.How to recover database?Can I get the steps?
You would not be able to drop it if it is in active state, did you meant it is corrupted? If yes then you can use below query
Alter database clear [unarchived] LOGFILE GROUP #;>
Best regards,
Rafi
http://rafioracledba.blogspot.com/
Make sure to backup your database after above activity.
Regards
Anurag

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The document says:
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Hi,
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Where are BLOB Files stored when using redo log files.

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