RE: [xml-dev] [Summary] Should Subject Matter Experts Determine XML Data

["Michael Kay" <mike@saxonica.com>]

> 
> Suppose I interview several Book SMEs. They tell me that a 
> Book is comprised of a Title, Author, Date, ISBN, and Publisher.

They are very likely to tell you that, and they are very likely to be wrong.

Your SMEs (I hate that abbreviation) are almost certainly using words
ambiguously, and it's your job to sort out what they mean. They will happily
say one minute "We published 15 books last year" and a couple of minutes
later "We have 20,000 books in the warehouse". If the context doesn't make
it clear, they will refer to the first kind of book as a "title", but they
will never say "the title of this title is 'Data Analysis'". And they won't
tell you until you ask that the book/title will acquire a second ISBN when
the paperback edition comes out.

In short, unless you are unusually lucky, your SMEs will use the terms of
their trade very casually without ever having realised that they are using
the same word to mean several different things, and different words to mean
the same thing.

(Incidentally, the one thing they probably won't tell you is that a book "is
comprised of" anything. They may use terms like "book" and "title" very
freely, but they will use them gramatically. Most of them have worked with
copy-editors.)

This isn't specific to your example. Try asking different people in an
airline what the word "flight" means.

Michael Kay
http://www.saxonica.com/