Kurt J wrote:
Ah I think I understand. So using /about/ is really not appropriate
for the sort-of on-demand generation of rdf that i'm doing. in that
http://dbtune.org/cmn/data/<composer> redirects to a sparql query for
describing <composer> and there wouldn't be a foaf:primaryTopic
property in that result. so to use /about/ i would want to generate
static rdf files (ie http://dbtune.org/cmn/data/WAGN.rdf) and host
them? is this what is done on dbpedia? is there a fancy programmatic
way of doing this from the rdf store?
Kurt,
I'm not entirely sure about what you are trying to achieve so I will run
down the typical check-list for getting /about/ to work on a simple RDF
view.
Assuming that you have installed a recent conductor vad, and rdf_mappers
vad you will automatically have an administration interface (conductor)
that will allow you create simple RDF views directly from DB tables in a
few clicks, and the /about/ virtual directory + required
rewrite/redirect rules courtesy of rdf_mappers.
If the /about/ virtual directory has not been altered then it will
automatically retrieve and display RDF data from remote or local stores,
hence we now need to ensure that local Virtuoso returns suitable RDF.
The simplest way to see how to create an RDF delivering endpoint is to
allow Virtuoso to do it for you from a database table. From the
conductor go to "Database" then "RDF Schema Object". Find a table that
you would like from RDF data from and click "Generate Single Mapping".
You will be to a page containing a SQL script to be run, note the following:
1. The necessary grants (as you have seen before)
2. The IRI class, which will contain the URI for accessing the data
3. The create graph statement which details the mapping from SQL table
to RDF.
4. The 4 create rewrite rules which instruct Virtuoso how to handle
certain clients/methods for accessing the to-be-created endpoint.
5. the virtual directory creation (vhost_define) using the rules from 4.
Once you hit the execute button and wait for confirmation that x number
of RDF manipulations were done you should be able to point your web
browser to a URL that resembles the URI from 2. above. This should
automatically redirect you to the /about/ service for viewing the RDF in
an HTML format.
Please let me know how this compares with what you have already achieved
and are trying to achieve and we will see if we can overcome your
current hurdles.
Regards, Rob.
--
Software Development
OpenLink Software
