I would consider the NPE when sort by score is not included a bug. There is the work around, that you mentioned, which is to have a compound sort which includes score.
The second issue though of disabling the ReRanker when someone doesn't include a sort by score, would be a new feature of the ReRanker. I think it's a good idea but it's not implemented yet. I'm not sure if anyone has any ideas about conditionally adding the ReRanker using configurations? Joel Bernstein http://joelsolr.blogspot.com/ On Fri, May 6, 2016 at 4:10 AM, Andrea Gazzarini <gxs...@gmail.com> wrote: > Hi guys, > I have a Solr 4.10.4 instance with a RequestHandler that has a re-ranking > query configured like this: > > <lst name="defaults"> > <str name="defType">dismax</str> > ... > <str name="rqq">{!boost b=someFunction() v=$q}</str> > <str name="rq">{!rerank reRankQuery=$rqq reRankDocs=60 > reRankWeight=1.2}</str> > <str name="sort">score desc</str> > </lst> > > Everything is working until the client sends a sort params that doesn't > include the score field. So if for example the request contains "sort=price > asc" then a NullPointerException is thrown: > / > //09:46:08,548 ERROR [org.apache.solr.core.SolrCore] > java.lang.NullPointerException// > //[INFO] [talledLocalContainer] at > org.apache.lucene.search.TopFieldCollector$OneComparatorScoringMaxScoreCollector.collect(TopFieldCollector.java:291)// > //[INFO] [talledLocalContainer] at > org.apache.solr.search.ReRankQParserPlugin$ReRankCollector.collect(ReRankQParserPlugin.java:263)// > //[INFO] [talledLocalContainer] at > org.apache.solr.search.SolrIndexSearcher.sortDocSet(SolrIndexSearcher.java:1999)// > //[INFO] [talledLocalContainer] at > org.apache.solr.search.SolrIndexSearcher.getDocListC(SolrIndexSearcher.java:1423)// > //[INFO] [talledLocalContainer] at > org.apache.solr.search.SolrIndexSearcher.search(SolrIndexSearcher.java:514)// > //[INFO] [talledLocalContainer] at > org.apache.solr.handler.component.QueryComponent.process(QueryComponent.java:484)// > //[INFO] [talledLocalContainer] at > org.apache.solr.handler.component.SearchHandler.handleRequestBody(SearchHandler.java:218)// > //[INFO] [talledLocalContainer] at > org.apache.solr.handler.RequestHandlerBase.handleRequest(RequestHandlerBase.java:135) > > /The only way to avoid this exception is to _explicitly_ add th/e "score > desc" /value to the incoming field (i.e. sort=price asc, score desc). In > this way I get no exception. I said "explicitly" because adding an > "appends" section in my handler > > <lst name="appends"> > <str name="sort">score desc</str> > </lst> > > Even I don't know if that could solve my problem, in practice it is > completely ignoring (i.e. I'm still getting the NPE above). > However, when I explicitly add "sort=price asc, score desc", as > consequence of the re-ranking, the top 60 results, although I said to Solr > "order by price", are still shuffled and that's not what I want. > > On top of that I have two questions: > > * Any idea about the exception above? > * How can I disable the re-ranking query in case the order is not by > score? > > About the second question, I'm thinking to the following solutions, but > I'm not sure if there's a better way to do that. > > 1. Create another request handler, which is basically a clone of the > handler above but without the re-ranking stuff > 2. Use local params for the reRankDocs... > > <lst name="defaults"> > <str name="defType">dismax</str> > ... > <str name="rqq">{!boost b=someFunction() v=$q}</str> > <str name="rq">{!rerank reRankQuery=$rqq reRankDocs=*$rrd* > reRankWeight=1.2}</str> > *<str name="rrd">60</str>* > <str name="sort">score desc</str> > </lst> > > ...and have (in case of sorting by something different from the score) the > client sending an additional params "rdd=0". This is working but I still > need to explicitly declare "sort=price asc, score desc" > > Any thoughts? > > Best, > Andrea > >
