Re: Searching OO Associations with RDBMS Persistence Models

From: Dmitry A. Kazakov <mailbox_at_dmitry-kazakov.de>
Date: Sat, 17 Jun 2006 10:38:30 +0200
Message-ID: <8t81v3t6ygsy.j993m7xjq7df.dlg@40tude.net>

On 16 Jun 2006 13:03:30 -0700, Aloha Kakuikanu wrote:

> Robert Martin wrote:

>> A logical connection between two endpoint is a list of circuits.  This
>> application object is transient because the connections come and go.
>> They aren't stored in the database.

>
> Assume network is an [indirected] graph.

Directed (consider ADSL, RFID etc)

> Then logical connection is a
> path in the graph.

No. That's routing issues. A connection is either peer-to-peer or multicast. It does not mention any nodes passed. Some protocols use dynamic routing.

> There is nothing challenging in modelling graph in
> RDBMS and creating application objects that correspond to paths in a
> graph.

Incidence matrix? Huh.

> Why "object id" is significant in this picture? |

Because an object can be mobile. Connection can obviously be described by a trivial relation between nodes. But it is an implementation detail in, say, a middleware, which deals with objects, not connections.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de

Received on Sat Jun 17 2006 - 03:38:30 CDT