Re: proposed test cases to document current behaviour of EXISTS in SPARQL

good morning;


> On 2016-06-18, at 01:31, Peter F. Patel-Schneider <pfpschneider@gmail.com> wrote:
> 
> EXISTS in SPARQL has quite a number of problems.  The substitution that it
> is based on results in suspect constructs in the SPARQL algebra and
> counter-intuitive results.  There are known differences in implementations
> of EXISTS for common situations.
> 
> Here are a number of proposed test cases for EXISTS with their current
> status as per the SPARQL 1.1 Query specification and with suggestions on
> what should be changed to fix EXISTS.  I'm willing to transform these into
> the syntax of the test case suite if that is going to produce an effect.

the general practice has been to fork the repository, implement the tests in a branch and open an issue on the topic.
the last perhaps in parallel and/or in connection with a pull request.

they should include the dataset content.

that way others can take the tests, run them and report on their experience.

> However, one problem is that some of the test cases produce internal
> constructs that are semantically ill-formed but that do not end up in the
> final output.  I don't know whether the test suite can describe this
> situation.

if those would violate some constraint in an internal data model which causes the test to fail, then they would be negative tests.





---
james anderson | james@dydra.com | http://dydra.com