Re: How to publish SPARQL endpoint limits/metadata?

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> I am not sure if I understand what you wrote. Are you saying that I should not make all data available through the SPARQL endpoint?

I think Pieter had a better formulation…that is having the datadumps next to the SPARQL endpoint.. 
> 
>>> 
>>> I now wonder how I can publish the fact that my SPARQL endpoint has a LIMIT and that is has a certain value.
>> 
>> I guess it will all depends on your endpoint backend (fuseki, virtuoso, OWLIM ,etc). Some comes with configuration files where you can set the limit of the maximum results.
> My question was not about how to configure limitations on the endpoint backend, but how to make those limitations known to users of the backend.

I understand better now ;) I have a similar issue while using a Linked Data Platform relying on sesame, where I still have to find out what is the maximum results allowed
by sesame. So, yes having an explicit knowledge of those limitations could help the users. 

> 
> Perhaps I need to elaborate on what I am thinking about... Let's say a user agent that is browsing or crawling the web comes across a dataset that is somehow interesting. Using the VoID metadata the agent can discover the URI of the SPARQL endpoint. With that knowledge, the agent can start querying the dataset for those data that it is interested in. Now it would be very nice to know the service limitations before the agent starts querying. Perhaps the service has some kind of access control, perhaps it is scheduled to be offline at the moment, perhaps it can return no more than 100 results per request... If limitations like these are known to the agent, the changes of successful communication will be much increased. And perhaps it will take some weight of the server too. 

Well, apart from dcat, sd and voID mentioned, I can suggest this api vocabulary [1], with properties like api:maxPageSize, api:endpoint.

Best,
Ghislain

[1]http://linked-data-api.googlecode.com/svn/trunk/vocab/api.ttl#