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RE: Unstructured vs. Structured (was: HL7 and patient records in RDF/OWL?)

From: Cutler, Roger (RogerCutler) <RogerCutler@chevron.com>
Date: Tue, 14 Feb 2006 12:54:45 -0600
Message-ID: <0C237C50B244FD44BE47B8DCE23A3052011C62EA@HOU150NTXC2MC.hou150.chevrontexaco.net>
To: "Jim Hendler" <hendler@cs.umd.edu>, "Pat Hayes" <phayes@ihmc.us>, "Gao, Yong" <YGAO@PARTNERS.ORG>
cc: public-semweb-lifesci@w3.org

OK, then is there a preferred term for what we call "semi-structured
data"?  That is, information that is structured but where the structure
is not easily determined and perhaps has not been formalized at all, but
for which a formalized structure could be defined?  For example, tables
in a spreadsheet?  We really care about this kind of thing, but I don't
want to confuse the issue by using terms that most people understand
differently.

Incidentally, from my personal experience the usage of the term
semi-structured, that is, binary blobs in structured databases, is not
very common.  Frankly, this is the first I have heard the term used in
that sense, but maybe I just don't run in the right circles.

-----Original Message-----
From: public-semweb-lifesci-request@w3.org
[mailto:public-semweb-lifesci-request@w3.org] On Behalf Of Jim Hendler
Sent: Monday, February 13, 2006 3:43 PM
To: Pat Hayes; Gao, Yong
Cc: public-semweb-lifesci@w3.org
Subject: Re: Unstructured vs. Structured (was: HL7 and patient records
in RDF/OWL?)


At 14:46 -0600 2/13/06, Pat Hayes wrote:
>>
>>The point I'm trying to make is this: The concept of "structuredness" 
>>is relative and context-sensitive.
>
>Hear, hear. Well said.
>
>Pat Hayes
>


FWIW, Structured, unstructured and semi-structured, although non-precise
concepts in common language and (esp) philosophy, have well-defined and
precise meanings in database jargon" -- most database books have decent
definitions that are consistent with:
  unstructured - NL text
  semi-structured - unstructured fields within a structured DB context
  structured - relational model (or similar) (those papers with
technical definitions tend to get ugly and recourse to relational
calculus, so these overly simplified definitions should suffice for now)
that said, in the spirit of this particular thread, I think we should be
careful and, if we mean to use it in a DB context, make it clear in any
document that uses the term (i.e. "structured database" v. 
"structured data" which are very different in some contexts)
    -JH

-- 
Professor James Hendler			  Director
Joint Institute for Knowledge Discovery	  	  301-405-2696
UMIACS, Univ of Maryland			  301-314-9734 (Fax)
College Park, MD 20742	 		  http://www.cs.umd.edu/~hendler
Web Log: http://www.mindswap.org/blog/author/hendler
Received on Tuesday, 14 February 2006 18:55:26 GMT

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