Re: SQL instead of XQuery

["Andrzej Jan Taramina" <andrzej@chaeron.com>]

Dimitry said:

> Usage of XQuery for processing of xml-data in DBMS
> is practically equal to existence of second, foreign query language.
> I propose to use SQL instead of it - let me introduce my view in
> http://sql50.euro.ru/sql5.ppt (707 Kb, slides #31-47).
> Accepting this proposals, we get smoothness between rational and xml.

Some points, in no specific order:

1) There is a big impedence mismatch between nested, networked data 
structures like XML and the table-based orientation of RDBMS's.  There are a 
lot of good reasons to store XML in an XML-based DBMS.

2) It's relational, not rational.  Come to think of it, it's not rational at 
all. ;-)

3) The XRX stack (XForms/REST/XQuery) is a very powerful set of technologies 
to develop and deploy complex applications about an order of magnitude faster
(both in dev and maint time) than even the latest of dyanamic languages.  SQL
does not fill the same role as does XQuery.  XQuery is turing completewhereas
SQL is not (I believe).

4) The slide deck is atrocious.  Go visit the Presentation Zen web site/blog 
and redo the whole thing from scratch.  Please don't inflict those slides on 
anyone.  And posting it in something web friendly like PDF or HTML instead of
a proprietary vendor format would be nice too.

5) XLang?  That went the way of the dodo a long time ago.

6) I think the comparison of XQuery to SQL is apples/oranges.  Nonsensical, 
in a word. But the idea of extending SQL to understand XPath constructs for 
where clauses and such does have some merit for when using a hybrid XML/RDBMS
data store.

7) Sounds like an academic approach, that has little understanding of the 
real world of application construction and maintenance.

> I'd like to listen your critique.

Remember, you asked! ;-)
Andrzej Jan Taramina
Chaeron Corporation: Enterprise System Solutions
http://www.chaeron.com