OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.

 


Help: OASIS Mailing Lists Help | MarkMail Help

 


 

   Re: [xml-dev] key constraint question

[ Lists Home | Date Index | Thread Index ]

Bill,

What you are trying to do (enforce that there is at least one occurrence
of element TableB whose "relationship" attribute value is "needed")
cannot be done with W3C Schema. 

Someone will be along very shortly to describe how Schematron can
enforce this.

Kind Regards,
Joe Chiusano
Booz | Allen | Hamilton

Bill Riegel wrote:
> 
> I am trying to define a serialized Database to XML, via a XML Schema.
> 
> Problem
> 
> Table A has two relations two Table B. One is required the other is
> optional.
> 
> How do I define that the TableB with relationship="needed" is mandatory.
> 
> I can define a unique constraint under TableA that indicates that
> TableB/primaryKey be unique. This would prohibit someone defining
> Two TableB's with the same relationship, i.e. two needed or two optional.
> 
> But I do not know how to ensure there is a TableB with the relationship of
> "needed".
> 
> Instance Document:
> 
> <TableA xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
> xsi:noNamespaceSchemaLocation="TestSchema.xsd">
>   <primaryKey>xx</primaryKey>
>   <TableB relationship="needed">
>     <primaryKey>yy</primaryKey>
>   </TableB>
>   <TableB relationship="optional">
>     <primaryKey>yy</primaryKey>
>   </TableB>
> </TableA>
> 
> Schema Document
> 
> <?xml version="1.0" encoding="UTF-8"?>
> <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema";
> elementFormDefault="qualified" attributeFormDefault="unqualified">
>   <xs:element name="TableA">
>     <xs:complexType>
>       <xs:sequence>
>         <xs:element name="primaryKey"/>
>         <xs:element name="TableB" type="TableB_Type" maxOccurs="2"/>
>       </xs:sequence>
>     </xs:complexType>
>   </xs:element>
>   <xs:complexType name="TableB_Type">
>      <xs:sequence>
>       <xs:element name="primaryKey" type="xs:string"/>
>     </xs:sequence>
>     <xs:attribute name="relationship">
>                 <xs:simpleType>
>                   <xs:restriction base="xs:token">
>                     <xs:pattern value="needed|optional"/>
>                   </xs:restriction>
>                 </xs:simpleType>
>     </xs:attribute>
>   </xs:complexType>
> </xs:schema>
> 
> Bill Riegel
> LandMark Graphics
> 713-839-3388
> 
> -----------------------------------------------------------------
> The xml-dev list is sponsored by XML.org <http://www.xml.org>, an
> initiative of OASIS <http://www.oasis-open.org>
> 
> The list archives are at http://lists.xml.org/archives/xml-dev/
> 
> To subscribe or unsubscribe from this list use the subscription
> manager: <http://lists.xml.org/ob/adm.pl>
begin:vcard 
n:Chiusano;Joseph
tel;work:(703) 902-6923
x-mozilla-html:FALSE
url:www.bah.com
org:Booz | Allen | Hamilton;IT Digital Strategies Team
adr:;;8283 Greensboro Drive;McLean;VA;22012;
version:2.1
email;internet:chiusano_joseph@bah.com
title:Senior Consultant
fn:Joseph M. Chiusano
end:vcard




 

News | XML in Industry | Calendar | XML Registry
Marketplace | Resources | MyXML.org | Sponsors | Privacy Statement

Copyright 2001 XML.org. This site is hosted by OASIS