[rus-wg] RUS Specification - operation results

[Sven van den Berghe]

Steven,

 I can see some cases where the purpose of a query is only to get one (or
more) RUSIds for further processing (e.g. updates) so returning a full
record is excessive.

Sven


"Steven Newhouse" <sjn5 at doc.ic.ac.uk> wrote:

>> The extract/fetch operations seem to return one or more full
>> RUSUsageRecords, would it be sensible to add parallel operations that return
>> just the ids?
> 
> I think you identify a need for just a single additional operation.
> 
> RUS::extractRecordsRUSId
> INPUT: XPath/XQuery
> OUTPUT: List of RUSIds
> 
> The existing operation RUS::extractSpecificRecords could then be used to
> extract the relevant records.
> 
> Following the initial extraction of the RUS Ids what would the client do
> with them? As there is no meta-data other than the ID one of the few
> things would seem to iterate over them to retrieve specific records in turn.
> 
> The list of RUSIds from one search operation could be compared to that
> of another... but then the two queries could be merged into one to yield
> the required (from the combined query) records in one go.
> 
>> The would be more efficient when the purpose is just to
>> determine existence and not necessarily examine contents.
> 
> Do you have additional use cases in mind as to what you would do with
> the resulting RUSIds?
> 
>> On a related note, I don't know XPath/XQuery well but I assume that it is
>> possible to do something like "extract all records that have been created in
>> the last month". Is this correct?
> 
> As the initial timestamp element in the RecordHistory follows a standard
> format it should be searchable by XPath/Xquery... but I'm not an expert
> in this.
> 
> Can anyone clarify what XPath/XQuery can dow with timestamps?
> 
> Steven

-- 
Sven van den Berghe
Fujitsu Laboratories of Europe
+44 208 606 4651