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Home -> Community -> Mailing Lists -> Oracle-L -> Re: bfiles
> 2) Recoverability was compromised as the data was stored inside and
> outside the database. It was possible that the systems could get out of
> sync.
I also think one of the key points of putting all the files into the database is recoverability - if all of your data has to survive no matter what (even media failures etc), you have to use a database with transaction logging mechanism. It's unreasonable to make hourly or even more frequent full backups of your files if you have 10TB of data. On the other hand, incremental backup based on file modification date has to scan through all the directories (i-node lists) in file system and copy modified files individually, so it will be slow as hell.
But when storing large amount of frequently manipulated LOB data inside the database, one of the problems I've hit is the amount of redo generated - we had to drop LOGGING idea for our LOBs in one project since otherwise we would have had over 1GB of redo generated per second in one of our projected system. On the other hand we could tolerate some data loss, and finally we went with a solution where files could be stored either inside the database or externally, there just was a flag in row specifying how the application server should get the file.
Tanel.
-- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------Received on Wed Apr 28 2004 - 04:08:30 CDT
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