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Re: [xml-dev] Caught napping!
> PaulT wrote:
> > Yes, we know that RDB does not solve the problem.
> > Honest.
> > But I'd put it slightly different.
> > "Almost all current SQL servers - kinda suck".
> > I can elaborate why, but that's not my point.
> Can *anyone* elaborate on this?
I can elaborate on particular problems
that I have with SQL servers ( like
'standard' compliance bullshit actually means
'rewrite it all the time, when porting from one
SQL server to another' ).
I can *not* explain why SQL is a poor shadow
or the true RM ( and I doubt that there is many
people, who can ).
> Fabian Pascal
> goes on at length about how SQL is a poor shadow
> of the true Relational Model, but I can't seem to
> find any specific criticisms on his web site.
> (Presumably he goes into detail in one of his
> books, but I'm reluctant to shell out the cash.)
> SQL has its obvious deficiencies, but based on
> my (admittedly limited) understanding of the
> relational model I don't see any gross divergences
> from mathematical theory. (Well maybe one: it
> works at a different level of the Boom hierarchy,
> returning a Bag instead of a Set unless you use
> SELECT DISTINCT).
Changing just one axiom in Euqlid's geometry
results it pretty much different universe.
There is no 'just one small difference', when
it comes to axioms.
I'd love to look at alternatives to SELECT,
( still based on RM ). I'm sure there were
some, we just don't know those views.
I'm 100% sure that's possible, because
recently I got to invent my own brutal regular
expressions and to my suprise, I've found that it
is possible. Hiawatha webserver has
them implemented. They are regular expressions,
but 'different' from what we know. They mix
.* and () into *
> [ earlier ]
> > 1. XML has no reasonable model behind it.
> > ( where it is? where is the math, 'mapped' into
> > some real stuff ( like it is with SQL and/or regexprs),
> > the stuff that I can run on my computer? )
> There's plenty of theory that's applicable to XML, you just have
> to look outside the W3C to find most of it. RELAX/TREX/RELAX-NG
> are based on very elegant mathematics; there's Dan Suciu
> and Mary Fernandez' work on semistructured data; there's
> all the work Anne Brueggemann-Klein and Derick Wood have done
> on DTDs, typesetting, and context matching; et cetera,
> et cetera. Even within the W3C, some of the top researchers
> in functional programming and type systems are working on
> the formal model for XQuery, and pretty much everything
> that James Clark has worked on has a solid (if not explicit)
> mathematical underpinning.
I'd love to see a link to that mathematical underpinning
on his website ( www.jclark.com ) or on w3c website.
If his stuff is based on some math - where are the links
to that math?
Michael Champion did explained the source of my confusion
better, than I can.
SQL guys reject Codd's name and XML guys reject
'hedge automata' e t.c.
I do belive that there XQuery may be
(first in XML world?) real serious stuff
I'd appreciate the urls to some, you know,
clear math ... about XQuery
... but when I've looked at XQuery itself ...
At least XPath is beautiful ;-) SQL was
also nice looking ;-)