Differing registries, and dates

[Paul Harrison]

On 2010-04 -01, at 12:47, Markus Demleitner wrote:
>
> Plus... I had suspected some interesting interference between
> oai:datestamp and the updated attribute on ri:Resource to be at the
> root of this.  This does not seem to be the case, but still: What's
> the general opinion on them?
>
> Here's my take:
>
> oai:datestamp is the date the resource record was last changed (in
> my system, you say "(re-)publish this resource", and the point in
> time that happens becomes oai:datestamp).  This is also the point in
> time relevant for the OAI operations ("from", "until").
>
> updated, on the other hand, reflects when the "resource" itself last
> changed; my intention here has been to update it only when queries
> might yield different results (e.g., new data is ingested into the
> underlying database; this becomes somewhat tricky because there are
> computed resources for which there is no ingestion, but never mind
> the details now).
>

The updated attribute should also be the date that the registry record  
itself was updated (not when the resource it points to was updated,  
though you might have a policy of changing this attribute when the  
resource has changed - possibly with updated description to note the  
change)

see http://www.ivoa.net/Documents/REC/ReR/VOResource-20080222.html#restype

Paul.

p.s. - consistent harvesting is still a problem however.....