RE: XSD to ER Diagram

David:
 
I hope you don’t mind if I say I find this scenario a little perverse.  
 
If your community of interest considers an E-R model an effective means of communication (as pointed out it can only represent a subset of XSD) why not publish your data requirements in the form of an E-R data model and then generate the XML schema from it?  Some participants might find the common E-R model a useful basis for producing a RELAX-NG schema or an SQL database design or other physical implementations.
 
In other words, why implement and then model?  Why not model first and then implement, in as many media as participants desire?
 
Embarcadero probably has the most to offer in this arena.  It allows you to specify your own set of standardized XSD data types, for instance.
 
Umodel is for UML, not E-R, although UML modelling tools can be used to represent E-R models if you have the discipline to restrict your use of UML features.  UML and XSD are a much closer match in terms of their respective feature sets, which is one reason why UML tools are more commonly seen when modelling for XML implementations.  But once again, it is usually the UML that is used to automatically generate the XML schema, not the other way around.
 
As for ERwin XML, the last time I saw it, it was their own format (not XMI or anything) for exporting and importing an ERwin E-R model, complete with graphical positioning information.  For instance, we used it to export a data model and run it against the names in a data dictionary so we could generate a French version from the English version (naturally we had to spread the entity boxes out a bit afterwards because the French names were longer – perhaps we should have gone in the reverse direction ;-)
 
Cheers
Jack Lindsey
http://www.dss-snd.gc.ca/publication/en/chap/chap00403.html
 

> Date: Fri, 22 Aug 2008 14:36:32 +1000> From: David_BANBURY@rta.nsw.gov.au> To: xmlschema-dev@w3.org> Subject: XSD to ER Diagram> > > Please excuse me if this query does not directly concern specific XSD> issues but I hope it is related closely enough to XSD development to be> worthy of the group's learned opinion.> > We are using XSD to define an XML file format for data interchange. As> such the schema is not directly related to a specific system or> database. The schema relies heavily on key-keyref relationships to> describe the relational structure of the data model. It has proven very> useful throughout development to present the schema as an> Entity-Relationship Diagram but deriving an ER Diagram directly from the> XSD has been problematic.> > Are there any tools available which will automatically generate an ER> Diagram from XSD?> > Thanks for any information you can provide.> > Regards,> David Banbury> > Traffic Systems Branch> Roads & Traffic Authority of NSW> Australia> > Tel: +61 2 8396 1417> Fax: +61 2 8396 1600> > Before printing, please consider the environment.> > IMPORTANT NOTICE: This e-mail and any attachment to it are intended only to be read or used by the named addressee. It is confidential and may contain legally privileged information. No confidentiality or privilege is waived or lost by any mistaken transmission to you. The RTA is not responsible for any unauthorised alterations to this e-mail or attachment to it. Views expressed in this message are those of the individual sender, and are not necessarily the views of the RTA. If you receive this e-mail in error, please immediately delete it from your system and notify the sender. You must not disclose, copy or use any part of this e-mail if you are not the intended recipient.> 
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Received on Saturday, 23 August 2008 01:20:24 UTC