ParseException, cause: Invalid character e in property path ?relation

[graue70]

I'm sending queries to the qlever backend from python and have a strange problem. The following queries usually work fine both when using the web UI and when running my code. However, every once in a while (not reproducible), there is an error when running them from my code. Here are some examples:

PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX wikibase: <http://wikiba.se/ontology#>
SELECT DISTINCT ?relation WHERE {
  wd:Q61834926 ?relation ?object .
  ?relation_entity wikibase:directClaim ?relation .
}

ParseException, cause: Invalid character e in property path ?relation

PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX wikibase: <http://wikiba.se/ontology#>
SELECT DISTINCT ?relation WHERE {
  wd:Q62025443 ?relation ?object .
  ?relation_entity wikibase:directClaim ?relation .
}

ParseException, cause: Invalid character d in property path wikibase:directClaim

PREFIX wd: <http://www.wikidata.org/entity/>                                                                                  
PREFIX wikibase: <http://wikiba.se/ontology#>                
SELECT DISTINCT ?relation WHERE {                                                                                                                   
  ?subject ?relation wd:Q6819833 .            
  ?relation_entity wikibase:directClaim ?relation .                           
}                     

ParseException, cause: Invalid character r in property path ?relation

PREFIX wd: <http://www.wikidata.org/entity/>
PREFIX wikibase: <http://wikiba.se/ontology#>
SELECT DISTINCT ?relation WHERE {
  ?subject ?relation wd:Q538847 .
  ?relation_entity wikibase:directClaim ?relation .
}

ParseException, cause: Invalid character : in property path wikibase:directClaim

The exception is probably thrown in this line. Unfortunately, I don't understand what VALID_CHARS means exactly or at least I don't understand how there could ever be e.g. an e in the error message.

What could be the problem? Could it have something to do with std::isgraph() and inconsistent locales on qlever systems?

[joka921]

I also stumbled upon this multiple times today for the first time. This seems to be new, I am onto this.
Did you also encounter this when using the QLeverUI? for me it only happened in the script and I am not sure whether this is because the script does something different or because the script simply sends many more queries.

[joka921]

Ok, can you try again on the wikidata-full instance?
I added some diagnostic information on this strange bug and now for my evaluations, all occurences of this strange bug have disappeared. Maybe you can confirm if I only was lucky or if there was something faulty with the Docker image previously used.

[graue70]

Did you also encounter this when using the QLeverUI? for me it only happened in the script and I am not sure whether this is because the script does something different or because the script simply sends many more queries.

I did not encounter this when using the QLeverUI, only from my code. I wondered about the same thing as you.

Ok, can you try again on the wikidata-full instance?

I will, but it might take until September 14th.

[graue70]

Ok, can you try again on the wikidata-full instance?
I added some diagnostic information on this strange bug and now for my evaluations, all occurences of this strange bug have disappeared. Maybe you can confirm if I only was lucky or if there was something faulty with the Docker image previously used.

@joka921 It seems to be fixed. I haven't encountered the problem again.

[graue70]

@joka921 It happened again today:

ParseException, cause: Invalid character a in property path ?relation. Valid chars is: 0000000000000000000000000000000001111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000Numerical value of character is a

ParseException, cause: Invalid character a in property path ?relation. Valid chars is: 0000000000000000000000000000000001111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000Numerical value of character is a

ParseException, cause: Invalid character r in property path ?relation. Valid chars is: 0000000000000000000000000000000001111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000Numerical value of character is r

[joka921]

Yes, it also just happened to me.
Did you work on the wikidata api? Can you try out if this also happens in the
wikidata-test api that @hannahbast recently built?
(https://qlever.informatik.uni-freiburg.de/api/wikidata-test)

This is really really strange and I have no good way of debugging this, but I will try my best.