- From: Jim Davis <jdavis@parc.xerox.com>
- Date: Tue, 17 Nov 1998 09:58:28 PST
- To: w3c-dist-auth@w3.org
If you have an opinion about whether or not DASL should support queries on structured properties *please* speak up in the DASL list, www-webdav-dasl@w3.org The rest of this email explains this further, and can be skipped if you already understand what DASL is and what a query on structured properties means for DASL. DASL is the search protocol for WebDAV, it allows one to find resources whose properties or content have values specified in the query, (e.g. find resources whose date modified is > 19 Nov 1998 and whose text contains "Halloween".) WebDAV property values may be plain strings, but they may also be structured values (expressed as XML elements on the wire). The best example of the latter is the WebDAV lock discovery property, but those who have proposed WebDAV properties for Dublin Core metadata would likely also use structured values. DASL as currently defined provides means for searching string valued properties but not within structured properties. Thus one can not search for resources based on the value of the lockscope or owner within a lock. As a special concession to the need to search for collection/non-collection resources, it provides an ad-hoc test to determine whether a resource is a collection. Thus the current DASL requirements ID does not include a requirement for queries on structured properties. We could say there is a rough concensus that there is no requirement, but that would be based on having only one or two opinions, scarcely a mandate. We'd like to hear from more people one way or the other. In addition, if you think there *is* a requirement for queries on structured values, please if possible, describe the layout of the property values you expect to search, and the kinds of tests you think you'd need. For further information: The DASL home page is http://www.ics.uci.edu/pub/ietf/dasl/ (Archived) mail messages of greatest relevance are: Structure criteria for DASL queries http://lists.w3.org/Archives/Public/www-webdav-dasl/1998JulSep/0087.html (tries to "make (or reopen) the case for defining a structure criteria (also called "structured query") in DASL.") Should DASL have structure queries? http://lists.w3.org/Archives/Public/www-webdav-dasl/1998JulSep/0113.html (Attempt to provoke discussion on the need for structured queries) If you want to contribute to the design of DASL structured criteria, there are two proposals on the table right now, or you can add your own. Please see initial proposal for structure criteria http://lists.w3.org/Archives/Public/www-webdav-dasl/1998JulSep/0095.html (Davis's proposal for syntax for structured criteria) Querying WebDAV Hierarchical Properties -- The Proposal http://lists.w3.org/Archives/Public/www-webdav-dasl/1998JulSep/0118.html (Babich's proposal for structured query.) Some background on the above what kinds of structure criteria are needed? http://lists.w3.org/Archives/Public/www-webdav-dasl/1998JulSep/0089.html (lists the structural features that must be testable) Querying WebDAV Hierarchical Properties -- Motivation http://lists.w3.org/Archives/Public/www-webdav-dasl/1998JulSep/0117.html (Design rationale for the Babich proposal) Jim ------------------------------------ http://www.parc.xerox.com/jdavis/ 650-812-4301
Received on Tuesday, 17 November 1998 13:00:11 UTC