[OASIS Issue Tracker] (OSLCCORE-143) OSLC query does not specify how oslc.orderBy affects the results

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    [ https://issues.oasis-open.org/browse/OSLCCORE-143?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=68842#comment-68842 ] 

David Honey commented on OSLCCORE-143:
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Relying on lexical ordering in an RDF serialization format seems to be the wrong thing to do:
1) RDF libraries such as Jena don't support determining ordering of the resultant RDF model.
2) It depends on specific RDF serialization types such as RDF/XML.

It seems to me that there are three choices for oslc.orderBy:
1) Remove it from the spec. I dislike this because there are existing implementations using it.
2) Describe its semantics for paged query results only.
3) Describe its semantics for both non-paged and paged query results.

#2 means that within a page of results, the order is not directly represented. Rather, a client consuming the container would have to perform its own sorting of members. However, it would yield the correct pagination order.

#3 requires that we include a specific property (such as the proposed oslc:order). It should be easy for servers to determine an order value and include it as a generated property of each member. This seems to add real value. It avoids dependence on lexical ordering of serialized RDF.

> OSLC query does not specify how oslc.orderBy affects the results
> ----------------------------------------------------------------
>
>                 Key: OSLCCORE-143
>                 URL: https://issues.oasis-open.org/browse/OSLCCORE-143
>             Project: OASIS OSLC Lifecycle Integration Core (OSLC Core) TC
>          Issue Type: Bug
>          Components: Query
>            Reporter: David Honey
>            Assignee: James Amsden
>
> OSLC Query 2.0 describes an oslc.orderBy query parameter. However, our returned results use unordered representations such as a list of statements with rdfs:member. If the query response is non-paged, then oslc.orderBy serves no purpose - a consumer cannot determine the order from the returned RDF.
> It potentially serves a purpose for a paged response (either LDPC paging, or OSLC paging), where the first page should contain a subset of the sorted members starting at the beginning and so on. The OSLC Query 2.0 does not describe this usage pattern so it's unclear whether anything more was intended.



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