[REBOL] Re: [DEV] Re: dbms3.r 01
From: greggirwin:mindspring at: 14-Jan-2002 13:13
Rod, Romano, Gabriele, et al
(This got longer than I intended, just so you know :)
I can see the value in pure RDB systems, though I've rarely used them.
Here's why. I'm a big believer in ADTs (Abstract Data Types) and the
impedance mismatch between Types/Objects/Structs and RDBs is something I try
to avoid at all costs. Yes, I have relationships in my data but most of them
are either 1-to-1 or 1-to-a-few type relationships. The 1-to-many (which I
call 1-to-infinite) case has been much less prevalent for me. In most of
those cases, we had an ADT/object which acted as a kind of "relationship
manager".
A pure RDB model (I know I'm talking in absolutes here) doesn't allow for
arrays (multi-valued values, which I call a 1-to-a-few relationship), which
is far more common than the 1-to-infinite relationship, at least in my
experience.
I want to do as little work as possible, at the application level, to store
and retrieve my data. I love the idea of a transparent persistent object
system, with the ability to define relationships not implied by an object
hierarchy, though most OODBMS I've looked at are far from transparent
because they try to be all things to all people.
A few years ago, I saw what I thought was a very well designed ORDBMS
(orbject-relational) product. It was called Cascade/DB, from Microquill.
Another company bought the product and it vanished from sight (and
Microquill couldn't name the company who bought it, as part of the deal). It
allowed for nested structures, nested tables, object references, and records
were, IIRC, variable length blocks of data separated by newlines, so you
could pull up the data in an editor without it being complete gibberish. I
think editing it manually would have been disastrous, but you could at least
see it.
I don't know that the row/column format, as a native "mode", buys you
anything. If you want to import/export data with other systems, I've always
found it easiest to have specific tools for those specific systems. As soon
as you get into nested structures, the model becomes burdensome when you try
to generalize it. Again, in my experience, real-time interaction with other
systems was rarely required. We did most data transfers in batch, polled, or
manual import/export fashion.
So, for me, I want a simple system that is tightly focused on storing and
retrieving REBOL data (probably simple blocks, blocks of name/value pairs,
and objects). It should handle up to maybe 50,000 records, though most cases
will be far less I imagine. The little things I've done so far have actually
worked well using native storage, but the scalability, robustness, and
multi-user aspect are something I'm concerned about for more critical uses.
--Gregg
