incubator-clerezza-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Hasan Hasan <ha...@trialox.org>
Subject Re: Bug in SPARQL query serialization
Date Mon, 03 Dec 2012 06:53:31 GMT
Hi Giuseppe

can you please provide an example of the query that you use and that I can
reproduce easily?
I will try to take some time this week to have a look.

Kind regards
Hasan

On Fri, Nov 30, 2012 at 5:36 PM, Giuseppe Miscione <
g.miscione@innovationengineering.eu> wrote:

> Hi all,
> I found a bug in the SPARQL query execution chain, specifically in the
> *org.apache.clerezza.rdf.core.**sparql.query.Query* objects serialization
> made with the *org.apache.clerezza.rdf.core.**sparql.query.impl.**SimpleStringQuerySerializer*
> methods.
> The problem comes from the fact that the javacc objects used for mapping
> triple patterns are not listed in the same order as in the original query
> string. *SimpleStringQuerySerializer* serializes patterns into the ouput
> string in the order returned by the javacc parser, and so the output string
> won't always be equivalent to the source one. Moreover, parsing multiple
> times the same query string will result in different output strings.
>
> This problem is even more annoying when executing (like in my case)
> queries on graphs enanched with Pellet reasoner, because it has obviuos
> difficulties in inferencing relations if the order of triple patterns in
> the query is not the provided one.
>
> I solved the problem in my environment by simply saving the original
> string into the parsed *Query *object and then making
> *SimpleStringQuerySerializer* returns this string, without any processing.
>
> Can anyone take a look at the serializer to find a maybe better solution
> to avoid this weird behaviour?
>
> Regards,
> Giuseppe Miscione
>
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message