Re: proposed additions for discovery, sorting, and typed values

Hello all, 

We in the RDF Schema working group are also working with typing the
nodes of query resources along similar lines...

Our spec won't be public for a week or two (i don't think)...but I look
forward to integrating the functionality between all of these, and I
have been watching all of the great work going into DASL very closely.

XML-Data does have some lovely data typing mechanisims that I thing
would work quite nicely with DASL and WEBDAV, for searching and in
general overall.  

Ideally, these different specifications could be fully interoperable
with each other, providing a standardized universal searching and
querying mechanism for the whole web -- and all over HTTP.
Beautiful.

keep up the good work, and consider me a resource if you have any
questions about the RDF schema spec when it arrives.

Thanks,

Lisa Rein
W3C RDF Schema Working Group
http://www.finetuning.com

Saveen Reddy (Exchange) wrote:
> 
> A few comments on your proposal, Jim ...
> 
> Schema Discovery:
> 
> The text describes a property for discovering which operators are supported.
> There's a particular case in which I'm interested here. Suppose a server
> offers searching on every resource -- making it easy for the client to
> perform searches, by essentially making every URI available as a search
> arbiter. In this case clients don't have to go find an arbiter -- they can
> whatever URI is at hand. Would the queryschema property have to be defined
> on each on of those resources? That seems like it be potentially a lot of
> data stored on each resource just to support the search method. A PROPFIND
> response that returned all properties might be very large when doen over a
> container (even if depth=1).
> 
> My feeling if such a property would work best only if there where a small
> number of arbiters. One way to get around this and yet have discoverability
> for all resources is to use the DASL: part of the OPTIONS response; it could
> point the client to a resource that has the relevant queryschema property.
> This would allow the information to exist for any resource without the
> burden of actually defining the property on each searchable resource.
> 
> Typing:
> 
> We may want to leverage typing work that is already being done in XML. For
> example, XML-Data defines a number of types and a mechanism for doing typing
> in XML:
> 
>         http://www.w3.org/TR/1998/NOTE-XML-data/
> 
> Not all of this document deals with typing but there is a nice section on
> it. These types are very oriented to the kinds of searches we are talking
> about -- they basically match simple data types we are all familiar with.
> 
> Thanks,
> -Saveen
> 
> -----Original Message-----
> From: Jim Davis [mailto:jdavis@parc.xerox.com]
> Sent: Wednesday, March 11, 1998 10:02 PM
> To: www-webdav-dasl@w3.org
> Subject: proposed additions for discovery, sorting, and typed values
> 
> DASL needs methods for sorting results and for schema discovery.  It also
> needs three valued logic and explicit typing.
> 
> I have proposals for how to do all these.
> 
> sorting is obvious, we add a sortby tag to the simplesearch.  The only
> tricky issues are 1) ensuring that one can also sort by 'relevance' as most
> full text search engines do, and 2) allowing one to sort up or down, and 3)
> finding a way to talk about differences in sorting order among various char
> sets.  My current proposal only addresses the first issue
> 
> schema discovery means the ability to determine, for a given server, not
> only what query syntax it supports, but what properties are searchable,
> sortable, etc.   I suggest the way to do this is to say that for each
> searchable resource (an arbiter, as the current draft calls it), for each
> query syntax it supports, it define a property whose value is the (query
> syntax specific) schema.  For the simple search, this would list the
> searchable properties, available operators, etc.
> 
> I have a detailed proposal for a set of tags to do this for simple search.
> 
> We need data types so we can tell the difference between the string "7" and
> the number 7.  (Perhaps Alan B will send some email explaining more on this
> point.)
> 
> We need three valued logic so we can search for e.g. resources where some
> properties might be undefined, and so we can handle things like divide by
> zero with clarity.  This means we also need constants for the true, false,
> and unknown values.
> 
> Rather than send my specific proposal as a huge email file I have placed it
> on the Web, in both Word and plain text.  The plain text was generated from
> the Word and is not as nicely formatted but hopefuly conveys the ideas.
> 
> Perhaps Saveen will be kind enough to pick up my Word file (that is, if he
> agrees with my proposals) and merge them into the official draft proposal.
> 
> I should admit that the current proposal shows the syntax but does not
> explain or justify it very well.  If you've worked with lots of search
> systems than it may make sense, but otherwise I'll have to add more
> language to it.
> 
> I just wanted to get it out now so there could be some discussion on the
> basic framework.  If there is agreement then we can pursue the details of
> syntax further.
> 
> Please see
> 
> http://www.parc.xerox.com/istl/members/jdavis/dasl-plus.doc
> 
> http://www.parc.xerox.com/istl/members/jdavis/dasl-plus.txt
> 
> Best regards
> 
> Jim
> 
> ------------------------------------
> http://www.parc.xerox.com/jdavis/
> 650-812-4301

Received on Monday, 16 March 1998 14:53:12 UTC