On Jul 10, 2009, at 7:44 AM, Morbus Iff wrote:
I think it might be useful to go with your first instincts, that a
book is a document, and then see how to best organize the
information you have about the book in support of some
application, rather than
But, in the FRBR model, the "book" (FRBR's "Manifestation") is not
the "final" or "complete" document (CouchDB's "document"). Were I to
strictly map "the book is a document", the CouchDB document would be
a "Work" comprising *hundreds* of different Expressions and
Manifestations and Items, forever spidering out. Consider "The
Hobbit" (a famous thought-experiment for FRBR) - it'd be one
mightily huge, single, JSON document, comprising every edition of
every book, every CD, every Rankin-Bass iteration on TV, VHS, and
DVD, the forthcoming 2011 movie, the two video games made for it,
etc., etc. The singular artistic endeavor that is "The Hobbit" is a
lot more than a single book - it's a very complex stress test for
any FRBR application.
actually I'm not talking about "The Hobbit" as a concept, a class of
individuals comprising all the books, CDs, YouTube videos, etc., I was
referring to the "The Hobbit", the green volume sitting on my shelf
with an n-bit address in the universe that my dog chewed.
As the FRBR modelers point out, the entities are easy but figuring out
all the relations is hard. There are so many, and they depend largely
on a world view. For example, I have this customer with a moving
business, she specializes in moving books. In her schema all that's
needed is height, width, depth, and weight. All this "Work",
"Manifestation", ISBN-code stuff is just fluff.
One way to view documents is to consider them like rows in a table
where you can have as many columns as you like.
http://www.frbr.org/2006/08/19
It would fit into CouchDB's model to have a JSON document this
large? It would grow ever larger if a user ever used the application
too - every user who owned a copy (an Item) of a "The Hobbit"
Manifestation (a book, a CD, a VHS, etc.) would add on an FRBR Item
to the existing JSON document, which itself may have numerous fields
and tags and etc.
It would be easily safe to say that, for an FRBR mockup of "The
Hobbit" in a single JSON document, the JSON document would have
thousands of objects, and then an additional object for each user
who ever owned it.
Is that "OK", whilst still allowing for quick lookups against it,
and allowing me to load a particular "The Hobbit" Manifestation (or
the entire Work, as necessary), without loading, say, all the Item
objects?
Ignoring FRBR entirely, I suppose the question is: how large can
a CouchDB JSON document get before it stops being useful?
--
Morbus Iff ( i subscribe to the theory of intellectual osmosis )
Technical: http://www.oreillynet.com/pub/au/779
Enjoy: http://www.disobey.com/ and http://www.videounderbelly.com/
aim: akaMorbus / skype: morbusiff / icq: 2927491 / jabber.org: morbus
