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Re: Definition of Navigational (was: The wisdom of the object mentors)

From: topmind <topmind_at_technologist.com>
Date: 26 Jun 2006 13:47:50 -0700
Message-ID: <1151354870.351137.245050@m73g2000cwd.googlegroups.com>


> > It is not much use to anybody to store the fact that they are on Floor 4, but nobody knows where on the floor.
>
> If the application is an android, this type of situation can arise and
> we don't want to bring it back to the lab to update its db's schema.

Android? And we thought losing a job to India was scary.....

> Frequently when persons unfamiliar with dbd see the tree view in its
> interface (it has a grid view also) they automatically assume the
> underlying data must be stored and limited to trees. Such isn't the
> case. Dbd can represent a thing in any number of "lists", "tables",
> "trees", "graphs", "networks", etc simultaneously without redundancy.

That would imply that it uses pointers. I am curious, how do you avoid orphan references when something is deleted? Do you traverse the entire graph to delete any references to the just-removed item? Do you "lock" the thing while this is happening? Or, is it single-threaded? I suppose for this kind of app that a few orphans won't matter much. A nightly batch job could clean them out. (Human dreaming may be just such a purge stage, according to some researchers.)

-T- Received on Mon Jun 26 2006 - 15:47:50 CDT

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