Missing results with UNION and FILTER about comunica

[github-actions]

Thanks for reporting!

[rubensworks]

Does the problem also occur if you remove the FILTER clause?

[dobbelap]

Does the problem also occur if you remove the FILTER clause?

no, it is explicitely triggered by the presence of a FILTER clause.
note that the original query where we discovered the problem had a much more complex filter clause including a user defined function. I just wanted to reduce the query to something more simple (and without user-defined functions) that still had the suspect behaviour. hence the bound(?e1) which looks a bit unnecessary indeed. But it does trigger the behaviour that should be investigated...

[rubensworks]

Ok, thanks for the clarification!

@jitsedesmet Could you have a quick look at this one? I suspect this is not related to sparqlee, but perhaps you can have a look to confirm this.

[jitsedesmet]

I had a quick glance at this issue and I don't think sparqlee is to blame. It seems like sparlee does not handle UNION so it would be weird if the effects of one UNION case would effect the result of another case solely by a sparqlee issue.