- From: <noah_mendelsohn@us.ibm.com>
- Date: Fri, 18 Nov 2005 09:39:31 -0500
- To: Bryan Rasmussen <brs@itst.dk>
- Cc: "'Michael Kay'" <mike@saxonica.com>, "'petexmldev@tech-know-ware.com'" <petexmldev@tech-know-ware.com>, "'xmlschema-dev@w3.org'" <xmlschema-dev@w3.org>
I understand, and although I don't speak officially for the workgroup, I want to be sure you feel that your suggestions are being heard. One thing that would help, if you have not already done so, would be to mail this suggestion to www-xml-schema-comments@w3.org, which is the official comments list for the schema specification. We formally review the comments received at that list, and we either open new trackable issues or ensure that issues we are already tracking cover them. Please make clear that you are specifically endorsing schematron as a solution, as otherwise the WG might just view this as just another request for some form of co-constraints, and that's been a tracked request for some time. I'm also copying David Ezell, or WG chair, on this reply. Thank you very much. -------------------------------------- Noah Mendelsohn IBM Corporation One Rogers Street Cambridge, MA 02142 1-617-693-4036 -------------------------------------- Bryan Rasmussen <brs@itst.dk> 11/18/2005 03:31 AM To: "'noah_mendelsohn@us.ibm.com'" <noah_mendelsohn@us.ibm.com> cc: "'petexmldev@tech-know-ware.com'" <petexmldev@tech-know-ware.com>, "'xmlschema-dev@w3.org'" <xmlschema-dev@w3.org>, "'Michael Kay'" <mike@saxonica.com> Subject: SV: SV: SV: SV: Schema help Well on the subject of co-occurence constraints I would just like to reiterate what I said earlier, with some extension: Given that there is likely to be some argument in W3C as to how far such constraints should be implemented I doubt they will come out as powerful as Schematron constraints, furthermore I have a hard time seeing this as producing a syntax as nice as Schematron, therefore I would really like to see something like: 1. XML Schema adopts Schematron as an extension language of some sort. 2. XML Schema puts some thought into how Schematron can be combined with XML Schema to the benefit of both, beyond the normal method of drop schematron in appinfo. I have some ideas on #2, but I'm somewhat conflicted about them - what model makes sense, syntax etc. so I don't really want to just blurt out with it. I'd be more interested in hearing what kinds of things other people could see connecting the two languages. Cheers Bryan Rasmussen -----Oprindelig meddelelse----- Fra: noah_mendelsohn@us.ibm.com [mailto:noah_mendelsohn@us.ibm.com] Sendt: 17. november 2005 18:51 Til: Bryan Rasmussen Cc: 'Michael Kay'; 'petexmldev@tech-know-ware.com'; 'xmlschema-dev@w3.org' Emne: Re: SV: SV: SV: Schema help Well, I think there are good reasons from time to time to revisit the effectiveness of the W3C process and the compromises embodied therein. I'm not convinced that a deep dive on that is the best use of this particular mailing list. I happen to like the working groups I've been on that do their work in public (in my case, both the TAG and XMLP) and I'd be happy for schema to go the same way. Then again, I really don't think that's a substitute for having people who have 30% of their time committed to working on a technology. There's a lot of detail work and care required to revise a specification even if there's agreement on the general ideas. The discussions need to involve people who have the knowledge and the time commitment to work through interactions with existing features of the specification. In the case of co-constraints, it would seem to me that there ought to be a careful look taken at the relationship between the existing key/keyref/unique constraint mechanisms and anything new that's proposed. It would be nice to believe that we wouldn't just be sprouting new and uncoordinated ways of doing things every few years. So, I personally welcome broader input, but what we're really short of are the people who can edit the specification text, draft prose, be responsible for the details, etc. Of course, there are also lots of other messy issues to consider when you change the working mode of a group including anti-trust laws in various jurisdictions, IP issues, etc. If people feel that they have ideas for how the W3C can do these things better, I think the right place to go would be to the W3C staff and/or the workgroup chairs. I personally would not be against having the schema WG switch to using a public mailing list for its discussions. I suspect that requires a recharter, but in principle I'm fine with it. I don't think that will solve much of our resource problems. We don't lack for people with good ideas, in email or in person. We're missing the people to do the archticture and drafting work that goes into making all the details fit together. It's hard to do that well without meeting F2F from time to time. -------------------------------------- Noah Mendelsohn IBM Corporation One Rogers Street Cambridge, MA 02142 1-617-693-4036 -------------------------------------- Bryan Rasmussen <brs@itst.dk> Sent by: xmlschema-dev-request@w3.org 11/17/2005 04:59 AM To: "'Michael Kay'" <mike@saxonica.com> cc: "'xmlschema-dev@w3.org'" <xmlschema-dev@w3.org>, "'petexmldev@tech-know-ware.com'" <petexmldev@tech-know-ware.com>, (bcc: Noah Mendelsohn/Cambridge/IBM) Subject: SV: SV: SV: Schema help Damn, an earlier typo in the email address of Pete Cordell added in by me was replicated in your email. Just on the off chance this thread goes any further I thought I should correct it. I've cc'ed Pete on this mail. Sorry for the problem. Cheers, Bryan Rasmussen -----Oprindelig meddelelse----- Fra: Michael Kay [mailto:mike@saxonica.com] Sendt: 17. november 2005 10:47 Til: noah_mendelsohn@us.ibm.com; Bryan Rasmussen Cc: xmlschema-dev@w3.org; ',petexmldev@tech-know-ware.com' Emne: RE: SV: SV: Schema help > 1) Although most widely used schema validators are fairly > slow, one can in > fact implement the XML schema rules at quite high speed. My team is > hoping to publish some work in that area in coming months, > and I suspect > that others in the industry are working in the same > direction. I think > it's important to the success of any technology we choose > that it be able > to meet the performance needs of our customers. I would resist this kind of thinking. SQL was successful because it put functionality first, and left implementors to devise optimisation strategies. Users need a constraint language that is capable of expressing arbitrary constraints on the content of a document, and it should be left to the implementor to work out which of these constraints can be evaluated in streaming mode and which can't. SQL today allows the full power of the query language to be used to express integrity contraints, and users learn when they need to restrict their ambitions to meet performance requirements. 90% of applications aren't performance critical anyway. There's no point telling users to go and use some other technology to do their validation, the other technology isn't going to be fast either. Michael Kay
Received on Friday, 18 November 2005 14:39:55 UTC