Thanks for the comments Murray! I do have a question on your suggestion:
> In my application I simply keep an XML validator (set up for
> well-formedness checking) hanging around and reuse it as
> necessary.
I am confused as to what this means. Does it mean:
a. Keep a mirror copy of the XML document local, do the insert into the mirror
copy,
and then check validation. If it's valid, only then update to the database.
[What's the point in having a database if it's being stored locally?]
b. Code into the application the data's business rules (i.e., what constitutes
valid
data) and thus it is able to check the data that is to be inserted.
[What's the point in having a DTD/schema if all the business rules have
been
stored into
the application?]
Could you elaborate upon what you mean when you say that the application checks
the
data? Thanks!
Isn't integrity checking a built in feature of all modern day (relational)
databases? /Roger
Murray Altheim wrote:
> Roger L. Costello wrote:
>
> > Hi Folks,
> >
> > I have noticed that, using XUpdate, I can insert bad data into a collection
> > XML
> > document. That is, before the data is inserted the document is valid;
> > after the
> > data is inserted the document is invalid . The document has a DOCTYPE
> > declaration so it seems reasonable to expect that the database would flag
> > the
> > bad data as an error. Is there some way to get the database to check the
> > data
> > prior to inserting it into the document, and to report an error if it would
> > make
> > the document invalid? /Roger
>
> Why would you want a database to do XML validation when it's
> simple enough to pre-validate content before putting it in?
> Constraint checking to that extent really isn't the province
> of a database, IMO, it's the kind of thing done at the application
> level.
>
> In my application I simply keep an XML validator (set up for
> well-formedness checking) hanging around and reuse it as
> necessary.
>
> Murray
>
> ......................................................................
> Murray Altheim <http://kmi.open.ac.uk/people/murray/>
> Knowledge Media Institute
> The Open University, Milton Keynes, Bucks, MK7 6AA, UK
>
> If you're the first person in a new territory,
> you're likely to get shot at.
> -- ma
