unresolved MPEG-7 queries/issues

I'm resending four questions which I sent in an earlier email

(http://lists.w3.org/Archives/Public/www-xml-schema-comments/2001JanMar/
0000.html)
 
which remain unanswered. I'd appreciate your advice.

regards,
jane

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1. Global attributes

When referring to a global attribute whilst declaring a local 
attribute,
can you modify its "use" attribute value and expect this to overwrite 
the
original value?

Ex:

<attribute name="myAtt" type="integer"/>

<complexType>
   <!-- can we expect the default value, 0, is specified
        in the following local attribute? -->
    <attribute ref="myAtt" use="default" value="0"/>
</complexType>

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2. Root Elements

Is there a recommended way to specify a root element amongst global 
elements in an instance document ?

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3. Is it possible to derive an abstract complexType from a non-abstract
complexType?

------------------------------

4. Using derivation by restriction, can we change the content model of 
a group
from choice[0,n] to sequence?

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Received on Monday, 26 February 2001 21:06:40 UTC