Fwd: XMLSchema

Here are the comments I received from Mike Stonebraker.  I have other 
within Informix looking at the document to see how they would affect the 
OR, Object Relational Model.

I Hope this is the correct list to submit these comments on.  Let me know 
if I need to do something else.

Thanks,

chuck



>X-Sender: mike@pop.cohera.com
>X-Mailer: QUALCOMM Windows Eudora Pro Version 3.0.5 (32)
>Date: Fri, 26 May 2000 09:17:19 +0100
>To: herbach@informix.com
>From: Mike Stonebraker <mike@informix.com>
>Subject: XMLSchema
>Cc: campbelc@informix.com, cto@informix.com
>
>I come from the following point of view.
>
>It must be possible to map XMLSchema into an OR Schema, so that a
>"shredder" will work.  In addition, it is highly desirable if the OR schema
>can be updated directly (and not through XML).  For example, one might want
>to directly enter purchase orders and then export them as XML objects,
>obeying XMLSchema.
>
>Hence, it is desirable if XMLSchema constraints can be mapped to OR
>structural constraints and not supported by an ingest function.
>
>In this regard, the following stuff seems problematic:
>
>1) minoccurs and maxoccurs  -- there is no corresponding SQL construct
>
>2) choice -- this is basically to support union types, and SQL doesn't have
>them
>
>3) all -- allows items to appear in any order, and XML is order sensitive.
>Not clear that there is an easy way to support this....
>
>4) equivalence -- allows two types to be declared equivalent -- no
>corresponding construct in SQL.
>
>There are probably some more cases that are ugly -- these are just the ones
>that occured to me on a quick reading of the XMLSchema document.
>
>/mike

=====================================================
Charles E. Campbell    ---   Standards &  Language Architect
Informix Software, Inc.      Phone +1.510.628.3908
300 Lakeside Drive             Email: campbelc@informix.com
Oakland, CA 94612            Fax:  +1.510.628.3736
USA
                                        Personal FAX +1.916.988.6092
                               Personal Phone +1.916.988.3501
                                         Personal Cell +1.916.300.1205
                               Personal email: campbelc@ix.netcom.com
=====================================================
= Any opinions expressed are the opinions of myself and may or may
= not reflect the opinions of  anyone else or the company I represent.
=====================================================

Received on Saturday, 27 May 2000 02:21:22 UTC