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Your entire argument is incorrect. A decimal type can hold and represent
1.1 with ease. A floating point type cannot accurately represent 1.1.
PITHY WORDS OF WISDOM
Let sleeping dogs lie, unless they snore.
This posting is provided "AS IS" with no warranties, and confers no
> -----Original Message-----
> From: Rick Jelliffe [mailto:email@example.com]
> Sent: Wednesday, December 04, 2002 9:58 PM
> To: XML DEV
> From: "Jonathan Robie" <firstname.lastname@example.org>
> > My question was:
> > "Why does the presence of a data type prevent reuse, since you can
> > always throw it away? Can you show me an example where this
> causes problems?"
> > The data type provides additional information about the
> data. You can
> > feel free to discard this information if you don't need it,
> or to use
> > it to reinterpret the data, or to use the data as is. I am
> trying to
> > think of a concrete example where the presence of this data
> really gets in the way.
> My perspective is slightly different than Jonathan's or
> Uche's nominal positions.
> The concrete example is the one currently under discussion in
> various places: that in XML Schemas datatypes you cannot
> represent any exact amounts that have decimal positions. So
> the decimal "1.1" is not the exact number 1.1. This will be
> well-known to most people who have done undergraduate
> computer science, and for a catch up, see Sun's BigDecimal
> As soon as I fix the datatype xs:decimal to the type "1.1" I
> am fixing its value and precision to something different than
> almost any "average"
> user will be expecting. And whether I can "throw away" that
> typing (i.e., adopt the natural typing that conforms to
> "average" user's expectation) depends entirely on the
> particular situation, it seems to me. (There is no need to
> adopt either extreme, unfortunately, that datatyping can
> always be thrown away or that datatyping can never be thrown away.)
> Jonathan's escape clause is to say "well, xs:decimal is not
> really the correct datatype" but what else is there? A
> restricted version of String will result in these numbers
> being unusable as numbers in standard query languages.
> Sorry to be a broken record, but WXS' pretence at being a
> universal schema language (rather than adopting a modular,
> extensible design) and its adoption by other technologies
> means that we have to judge it far more crtitically than less
> grand systems.
> Rick Jelliffe
> P.S. For a possible alternative set of datatypes, you may be
> amused by http://www.topologi.com/public/alternateDatatypes.html
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