[xquery-talk] XQuery and SQL opinion

[Ronald Bourret]

I pretty much agree with what Jim says. A couple of comments:

1) I think Jim is right that big RDBMS companies will dominate the
XQuery field. There are several reasons for this. First, those companies
have a lot of money and expertise to throw at both implementation and
marketing. Second, they have large, well-heeled customer bases who would
be better served by staying with an existing product than moving to a
native XML database. And third, they are in a better position to
integrate relational data and XML than the native XML databases, both
because of the fact that they own the SQL engines and because their
customers own the data.

(This prediction assumes that the XML data type in SQL/XML will
eventually be implemented by native XML technology -- it's currently
implemented in both IBM and Oracle as a CLOB. I can't think of any
reasons that the big RDBMS companies won't eventually do this --
performance will be horrible otherwise.)

2) I think that the statement that new XQuery applications will overtake
new SQL applications by 2010 or 2012 is credible, but perhaps a bit
misleading. The implication is somehow that SQL is going away. Given the
durability of, say, COBOL, I doubt this will happen. So while this might
be true for *new* applications, I don't think it will be true for total
applications. That is, SQL is a good fit for most of what it is used for
today and those applications will be around for a long time to come.

(An interesting question is what conditions would make the total number
of XQuery applications overtake the total number of SQL applications. It
implies either that people do everything through XML or that the set of
data we are using with databases changes considerably to favor
semi-structured and unstructured data over relationally structured data.
I'm hard-pressed to believe the first scenario for performance reasons
-- I think SQL will always outperform XQuery -- but the second scenario
would posit a very interesting future indeed.)

3) I find it curious that Jim seems to lament the cessation of
significant growth in SQL. Does software that stops growing actually
die? It certainly loses its sex appeal -- people do tend to flock to
what is new -- but big, sober customers like banks tend to stick with
what works. Look at the continued use of hierarchical databases, ASCII,
and COBOL, for example.

-- Ron

Jason Hunter wrote:
> 
> http://otn.oracle.com/pub/columns/melton_sql.html
> 
> An opinion piece by Jim Melton.  For the XQuery-related content, jump
> ahead to the "SQL and XML: Glimpse into the Future" section toward the end.