Re: What is the logic of storing XML in a Database?

From: David Cressey <cressey73_at_verizon.net>
Date: Fri, 30 Mar 2007 12:11:07 GMT
Message-ID: <v77Ph.2066$NO.1220_at_trndny05>


"Bernard Peek" <bap_at_alpha.shrdlu.com> wrote in message news:slrnf0puka.tel.bap_at_alpha.shrdlu.com...
> On 2007-03-30, Cimode <cimode_at_hotmail.com> wrote:
>
> >> If all database systems had a standard interface to do that with then
we
> >> could just connect the databases together and move data around.
> >>
> >> In fact there are already two systems that do that. One is XML, the
other is
> >> ODBC. I understand that ODBC uses a primitive dialect of SQL to select
data
> >> for transmission. If it could be replaced by a better language then it
might
> >> be usable.
> > I am curious about this statement. More than 4 ou of 5 dbms's (namely
> > ORACLE, DB2, SQL Server) can perfectly communicate db to db using
> > ODBC, OLE DB or Native providers. Why exactly would XML be necessary
> > on all of them because one out of 5 minor technologies do not use
> > XML? Is there any *good reason* XML is necessary?
>
> I'm not sure that I would consider ODBC to be perfect. It can certainly
> transfer data and so could replace simple CSV formats. But XML can also
> incorporate information about constraints and relationships, I don't
believe
> ODBC can. If ODBC or similar can handle the communication then it's
probably
> preferable to XML. But as I said, I think it needs a more capable language
> than the one used on ODBC.
>
> There is a database dump format that exports the database structure and
data
> in the form of a single SQL command that can create it. If that only
> included standards-compliant SQL then it would be a better transfer mediam
> than eiher ODBC or XML. But if it contains code that isn't executable in a
> different SQL dialect its capabilities are more limited.
>
>
Ten years ago, DEC Rdb had an option to dump Rdb specific DDL or standard SQL.
I used that option to create Oracle databases that were logically equivalent to existing DEC Rdb databases. Received on Fri Mar 30 2007 - 14:11:07 CEST

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