Lists Home |
Date Index |
OK fair enough, Let's say you apps requires from a modern relational DB a
serialized XML version structured as RDF descriptions. So far so good, we
can make it easy so that a record equals an rdf description. Since an RDF
description is also a frame and a frame is simply a kind of record then it
could be done quite easily. Moreover, the XSQL or whatever RDB to XML
mapping tool you use will be probably simpler to write because of the simple
syntax of XML (when it is mapped to a record off course). Then to display
this record set an even make it sortable, create a XUL app containing a
table created from the treeView (In that case we display a tree with a
single level - an array).
a) Serialize a table into a collection of rdf description. The mapping is
quite easy; a description is equivalent to a record. I my result set
includes the fields (title, author, ISBN to name a few), they are simply
mapped to the rdf description children as <title>, <author> <ISBN>. Each URI
could be the key used to identify the record. Include a <base> element to
specify the base of the relative URI used as "about" attribute's value.
b) Create a simple XUL document including a table implemented from the
treeview component. Make it sortable if you whish with a simple attribute
setting and voila, you get a small app to start with. The treeview component
if bind to the rdf document is automatically constructed.
Note: if the RDB allows setting SQL statements into a URL then the binding
to the RDF document from the XUL component is quite easy: a single line.
Otherwise, you'll probably need to write a server side XSQL template> I
agree the last case is annoying but this problem is generalized to a lot of
XML technologies include XSLT and several others. I guess W3C members are
too busy counting how many angels can sit on the top of a needle to address
a concrete issue like this :-)
Another point: If more web components are made to understand a particular
format, then obviously one way to integrate disparate data is to translate
these data into that single format. For instance, XUL components understand
RDF description and consider them as record/frames. The component could be
bound directly to the RDB source (as it is the case for IE databound
components) or to a serialized version (as it is the case in XUL). If we
have a rich collection of components that prefer a certain serialized format
then that's it... To build the apps we use the format the components like.
Anyway, Elliotte be re-assured, too many people are sleeping on the switch
to make it a reality on the web. So, I guess we'll see a lot of water going
under the bridges before the sleeping beauty wakes up :-)
Didier PH Martin