Lexical error while using MINUS keyword in a sparql query

Question

I ran the following queries in SPARQL in Jena framework against an ontology ( The wasBornIn predicate is present in the ontology )

select ?p where 
  {
   ?s ?p ?o FILTER NOT EXISTS { ?s :wasBornIn ?o }
  }

and

select ?p where 
  { 
   { ?s ?p ?o } MINUS { ?s :wasBornIn ?o } 
  }

For the first query, I am getting the following errors :

null
Error: Lexical error at line 7, column 21.  Encountered: " " (32), after : "NOT"

and

null
Error: Encountered "<EOF>" at line 5, column 16.
Was expecting:
"{" ...

For the second query, I am getting a similar error :

null
Error: Lexical error at line 5, column 38.  Encountered: " " (32), after : "MINUS"

Both the queries seems to be correct and I've no idea why I am getting those errors.

Where's the code that's actually generating the query. I wouldn't be surprised if at least some of it is some string concatenation with some spaces missing. E.g., `"?s ?p ?o" + "FILTER NOT EXISTS …"` producing `?s ?p ?oFILTER NOT …` with a variable `?oFILTER`. — Joshua Taylor, Apr 02 '14 at 18:52
I am not passing the query in the form of string. I am directly typing in the actual query. @JoshuaTaylor — galahad, Apr 04 '14 at 09:15
Directly typing into what? You said that you were doing this with jena… we will need to see the code before we can't say anything else. As I mentioned in an answer both of the queries themselves are well formed. — Joshua Taylor, Apr 04 '14 at 11:46
I am typing the query in the output console of NetBeans. However I figured out the problem. The queries are valid as you said but turns out I understood the meaning of MINUS wrongly. I got it now. Thanks for the help @JoshuaTaylor — galahad, Apr 09 '14 at 06:08

Joshua Taylor · Accepted Answer · 2014-04-02T20:28:11.130

You first and second queries (assuming that you've got the : prefix defined) are legal. You can check with sparql.org's query validator. E.g., these are both legal:

prefix : <>

select ?p where 
  {
   ?s ?p ?o FILTER NOT EXISTS { ?s :wasBornIn ?o }
  }

prefix : <>

select ?p where 
  { 
   { ?s ?p ?o } MINUS { ?s :wasBornIn ?o } 
  }

However, there's something you're not showing us; you're mentioning that there's an error in line 7 (for the first) one, but the query you've shown doesn't have 7 lines. Not only that, I'm not sure how you could encounter an EOF at line 5, and then still have a line 7 to get another error. Perhaps there's something different about the code that's actually constructing the query. Maybe you've got something like this:

"?s ?p ?o" + 
"FILTER NOT EXISTS { ?s :wasBornIn ?o }"

in which case you'd end up with

?s ?p ?oFILTER NOT EXISTS { … }

(i.e., with a variable named ?oFILTER). Without seeing your code, though, this would be hard to diagnose. You could also be parsing the query incorrectly, somehow.

Lexical error while using MINUS keyword in a sparql query

1 Answers1