Re: image database

I'm not involved with the application I'm about to describe myself, but I interviewed there once,
so I got introduced to it.

It's a database that stores images of people's retinas. By comparing a retinal image to a baseline, they are able to detect certain diseases much earlier, and that helps to save eyesight.

In this database the images were, as of about 5 years ago, being stored in the database. This was being run by a medical research outfit, located in the Boston area.

The database system in question is Oracle RDB. Oracle RDB is not to be confused with Oracle RDBMS, which everyone knows as simply "Oracle". Oracle RDB was acquired from Digital Equipment Corp. which had developed and sold it as DEC RDB, among other names.

Oracle RDB has provisions for BLOBs (Binary large Objects) and does a very good job in handling the tradeoffs between how you want to store and retrieve BLOBS as opposed to more "relational friendly" datatypes. It also integrates BLOBs into the whole atomic transaction, rollback, roll forward, synchronization, and database backup functionality that makes a database reliable in the face of unplanned events.

Oracle RDB is not very well known, even inside the Oracle company. But you should definitely look at it as part of your survey.

Jerry Gitomer wrote in message <20000622.6104300_at_p200.nodomain>...

I developed one such system and have been the DBA for two others. In all cases the images were stored outside of the database as flat files and the database carried structured information about the images along with their file addresses.

From what I see in the newsgroups people who are storing the images in the database itself tend to suffer performance problems. I suspect this is because RDBMS were never intended to accommodate extremely large records in the first place. In particular operations that require a full scan of the table containing the images tends to be painfully slow. By separating the images from the information about them this pain can be avoided.

>>>>>>>>>>>>>>>>>> Original Message <<<<<<<<<<<<<<<<<<

On 6/21/00, 9:16:44 AM, "a.p." <picus_at_libero.it> wrote regarding image database:

> I'm looking for people working on image database, to exchange
 eperiences
> about image indexing and query optimization.
> Thank you
> Antonio Picariello
Received on Thu Jun 22 2000 - 00:00:00 CEST