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From Hasan Hasan <>
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

On Fri, Nov 30, 2012 at 5:36 PM, Giuseppe Miscione <> 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

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