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blob

Steve Bear_1
Frequent Advisor

blob

we are in the process of evaluating BLOB to store files/binary objects in the database at a large scale (for doc archiving purposes) .

Can any one point me to the appropriate documentation on BLOB. like pro and cons using BLOB. Any specific issue any one aware of related to BLOB and any specific performance issues ?? any issues from implementation and administration point of view?

Any suggestion will be appreciated.
Thanks,
1 REPLY
Jean-Luc Oudart
Honored Contributor

Re: blob

From a Metalink forum thread :
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Images can be stored as bfile of BLOBs in the database.
BLOBs are generally a better choice.

Here is a comparision between the two.
Storing images in a BFILE versus a BLOB.
Security:
BFILEs are inherently insecure, as insecure as your operating system (OS).
Features:
BFILEs are not writable from typical database APIs whereas BLOBs are.
One of the most important features is that BLOBs can participate in transactions and are recoverable. Not so for BFILEs.
Performance:
Roughly the same.
Upping the size of your buffer cache can make a BIG improvement in BLOB performance.
BLOBs can be configured to exist in Oracle's cache which should make repeated/multiple reads faster.
Piece wise/non-sequential access of a BLOB is known to be faster than a that of a BFILE.
Manageability:
Only the BFILE locator is stored in an Oracle BACKUP. One needs to do a separate backup to save the OS file that the BFILE locator points to. The BLOB data is backed up along with the rest of the database data.
Storage:
The amount of table space required to store file data in a BLOB will be larger than that of the file itself due to LOB index which is the reason for better BLOB performance for piece wise random access of the BLOB value.
Please refer to online documentation -->Oracle8i Server Application Development-->Oracle8i Application Developer's Guide - Large Objects (LOBs)

Regards,
Jean-Luc
fiat lux