The syntax error was correct even in the current stable version
The problem was that the code for converting from an algebra back into a query usually puts top level BIND as project expressions which in most cases is semantically equivalent to the original query. However when there is a GROUP BY present it needs to recreate the BIND as an actual BIND or you get the variable scope error. In algebra terms a project expression and a BIND at the top level of the query pattern are semantically equivalent bar the above proviso about interaction with GROUP BY Rob On 4/1/13 7:47 PM, "Diogo FC Patrao" <[email protected]> wrote: >Hello Rob > >Should now be fixed, build from latest Trunk or wait 24 hrs or so for the >> snapshot to get build and deployed by the Apache build server >> > >* THANKS a million * ! I'm running a couple of experiments for my PhD >thesis, and was getting the excuses done, for that bug messed up part of >my >data. Now I can get everything right. Thanks, thanks. > > >> What version of ARQ are you using to do the OpAsQuery? I assume >> 2.10.1-SNAPSHOT since turning this type of query from its algebra back >> into a query only very recently became possible. Previously the BIND >> would have been lost completely when converting back from an algebra to >>a >> query. >> > >The jar file says "2.10.0", I just downloaded the latest stable version. > > >> Also is there a reason you are using ARQ 2.8.8 in your system? That's >> very out of date (about 2 years so) now. >> > >well, I'm running this experiment for one year and two months now, and >just >copied the binaries and stuff that were working. TLDR: lazy. > >anyway, 2.10.0 ARQ yielded the same error. > >However, should defining an alias on the query head allow referring to it >elsewhere? Are alias and BINDs really equivalent? MySQL have this >behaviour, but not Oracle. > >Thanks (again). > >dfcp > > > > >> Andy - The report states that the query is passed off to a system >>running >> 2.8.8, even with this fix did ARQ support BIND syntax that far back? >>I.e. >> will this fix just move the error elsewhere? >> >> Rob >> >> >> >> On 4/1/13 12:42 PM, "Andy Seaborne" <[email protected]> wrote: >> >> >Hi there, >> > >> >Thanks for the report. I've captured this as: >> > >> >https://issues.apache.org/jira/browse/JENA-429 >> > >> > Andy >> > >> >On 31/03/13 21:11, Diogo FC Patrao wrote: >> >> Hello >> >> >> >> I was performing a simple test with OpAsQuery: >> >> >> >> Here is the original query: >> >> >> >> PREFIX : <http://www.cipe.accamargo.org.br/ontologias/h2tc.owl#> >> >> PREFIX xsd: <http://www.w3.org/2001/XMLSchema#> >> >> PREFIX mylib: <java:dateadd.lib.pkgfor.arq.> >> >> >> >> SELECT ?yearmonth ( count(?document) as ?total ) >> >> WHERE >> >> { >> >> ?document a :Document; >> >> :documentDateOfCreation ?date ; >> >> :documentType "exam results" . >> >> BIND( mylib:DateFormat( xsd:string(?date), "yyyy-MM" ) as >> >> ?yearmonth ) >> >> } group by ?yearmonth >> >> >> >> Then I ran the code below, that compile the algebra then render the >> >>query >> >> again. >> >> >> >> Query query = QueryFactory.create( that_query_above, >> >> Syntax.syntaxSPARQL_11); >> >> >> >> Op op = Algebra.compile(query); >> >> >> >> System.out.println(OpAsQuery.asQuery(op)); >> >> >> >> The result is below: >> >> >> >> SELECT (<java:dateadd.lib.pkgfor.arq.DateFormat>(< >> >> http://www.w3.org/2001/XMLSchema#string>(?date), "yyyy-MM") AS >> >>?yearmonth) >> >> (count(?document) AS ?total) >> >> >> >> WHERE >> >> >> >> { ?document <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> < >> >> http://www.cipe.accamargo.org.br/ontologias/h2tc.owl#Document> . >> >> >> >> ?document < >> >> >> >> >> >>http://www.cipe.accamargo.org.br/ontologias/h2tc.owl#documentDateOfCreati >> >>on> >> >> ?date . >> >> >> >> ?document < >> >> http://www.cipe.accamargo.org.br/ontologias/h2tc.owl#documentType> >> "exam >> >> results" >> >> >> >> } >> >> >> >> GROUP BY ?yearmonth >> >> >> >> However, this is not a valid query; notice that the BIND has gone, it >> >> somehow turned to a alias on query's head. >> >> >> >> ARQ 2.8.8. upon receiving this query, yields the error: >> >> >> >> Variable used when already in-scope: ?yearmonth in >> >> (<java:dateadd.lib.pkgfor.arq.DateFormat>(xsd:string(?date), >>"yyyy-MM") >> >>AS >> >> ?yearmonth) >> >> >> >> Is that a bug on ARQ or OpAsQuery? Or anything else? >> >> >> >> Thanks! >> >> >> >> -- >> >> diogo patrão >> >> >> > >> >>
