Hi Theo,

> For CLDType in case of collections with mixed contents it
> might be worth considering to add a an encoding scheme for a
> value that contain the number of items of a specific type:
>
> <dc:type>collection</dc:type>
> <cld:CLDType xsi:type="key-value">image=1000<cld:CLDType>
> <cld:CLDType xsi:type="key-value">book=1000000<cld:CLDType>
> <cld:CLDType xsi:type="key-value">article=50%<cld:CLDType>
>
> It looks horrible

;-)

> but it might help the user in using the CLD
> for finding his targets to search in.

I can see that providing this information in a structured form could be
valuable for resource discovery, but if we decided to support this in
the DC CD AP, I think we'd need to consider how best to model/represent
it.

I'm inclined to say it isn't an appropriate value for the dc:type
property: the value of dc:type is always a class (or a "value string"
which represents that class - "Text" for the class dcmitype:Text, and so
on). And the use of dc:type in a statement always says "This resource is
an instance/member of that class".

I suppose it could be argued that "image=1000" represents the class of
collections of 1000 image items, but I think it's really stretching the
use of dc:type - that's what I meant in an earlier message about not
"overloading" the type mechanism with information that we should really
provide by other means.

If it is really a requirement to be able to state the collection size in
terms of numbers of items of specific types, then it seems to me we need
to consider something like a "Collection Size"(?) encoding scheme which
would define values for dcterms:extent.

I think to model it properly might be quite complex e.g. the size (the
value of dcterms:extent) isn't just one number-of-items/item-type pair;
it's the aggregation/combination of several such pairs. So (written in
"fully striped" RDF/XML) you'd end up with something like

<dcmitype:Collection>

   <dcterms:extent>
      <some:CollectionSize>
         <some:itemCount>
            <some:ItemCount>
               <some:count>1000</some:count>
               <some:itemType rdf:resource="&dcmitype;Image"/>
            </some:ItemCount>
         </some:itemCount>
         <some:itemCount>
            <some:ItemCount>
               <some:count>1000000</some:count>
               <some:itemType rdf:resource="&dcmitype;Text"/>
            </some:ItemCount>
         </some:itemCount>
      </someCollectionSize>
   </dcterms:extent>

</dcmitype:Collection>

which is even more horrible!

Pete