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Re: IDREFS types in schemas

From: Hans Teijgeler <hans.teijgeler@quicknet.nl>
Date: Wed, 24 Dec 2003 23:11:42 +0100
To: "Henry S. Thompson" <ht@cogsci.ed.ac.uk>
Cc: Morgane Erenati <morgane.erenati@wanadoo.fr>, xmlschema-dev@w3.org
Message-id: <3FEA0F1E.2410BD38@quicknet.nl>
Dear Henry,

On Dec. 4th 2002 a person of the Altova (=Spy) helpdesk wrote me:

QUOTE

ID/IDREF datatypes are  present in XML Schema only for compatibility reasons with
respect to DTDs. They should NOT be used under normal
circumstances, except when the goal is to model behavior of an existing DTD.
Specifically they should NEVER be used together with key/keyref as
this will create total confusion, because now you have two separate mechanisms
trying to do the same thing mixed together with weird
consequences.

UNQUOTE

I do not sense that from your reply below. What is the official party line?

Regards,
Hans

==================================

"Henry S. Thompson" wrote:

> xs:ID (I think that's what you want for inp), xs:IDREF and xs:IDREFS
> function the same as they do in DTDs -- see any introductory XML book
> for details.
>
> Something like
>
> <xs:element name="GInP">
>  <xs:complexType>
>   <xs:sequence>
>    . . .
>   </xs:sequence>
>   <xs:attribute name="inp" type="xs:ID" use="required"/>
>  </xs:complexType>
> </xs:element>
>
> <xs:element name="Correspondance">
>  <xs:complexType>
>   <xs:sequence>
>    . . .
>   </xs:sequence>
>   <xs:attribute name="corresplist" type="xs:IDREFS"/>
>  </xs:complexType>
> </xs:element>
>
> or maybe I have the attributes on the wrong elements, I wasn't sure
> from your description.
>
> See the Primer [1] for an overall introduction to elements and types,
> and also the more powerful schema-native key and keyref.
>
> ht
>
> [1] http://www.w3.org/TR/xmlschema-0/
> --
>   Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
>                       Half-time member of W3C Team
>      2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440
>             Fax: (44) 131 650-4587, e-mail: ht@cogsci.ed.ac.uk
>                      URL: http://www.ltg.ed.ac.uk/~ht/
>  [mail really from me _always_ has this .sig -- mail without it is forged spam]

Received on Wednesday, 24 December 2003 17:09:42 GMT

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