Hello carlos, could you show us how your Solr-call looks like?
Regards, Em Am 16.02.2012 14:34, schrieb Carlos Gonzalez-Cadenas: > Hello all: > > We'd like to score the matching documents using a combination of SOLR's IR > score with another application-specific score that we store within the > documents themselves (i.e. a float field containing the app-specific > score). In particular, we'd like to calculate the final score doing some > operations with both numbers (i.e product, sqrt, ...) > > According to what we know, there are two ways to do this in SOLR: > > A) Sort by function [1]: We've tested an expression like > "sort=product(score, query_score)" in the SOLR query, where score is the > common SOLR IR score and query_score is our own precalculated score, but it > seems that SOLR can only do this with stored/indexed fields (and obviously > "score" is not stored/indexed). > > B) Function queries: We've used _val_ and function queries like max, sqrt > and query, and we've obtained the desired results from a functional point > of view. However, our index is quite large (400M documents) and the > performance degrades heavily, given that function queries are AFAIK > matching all the documents. > > I have two questions: > > 1) Apart from the two options I mentioned, is there any other (simple) way > to achieve this that we're not aware of? > > 2) If we have to choose the function queries path, would it be very > difficult to modify the actual implementation so that it doesn't match all > the documents, that is, to pass a query so that it only operates over the > documents matching the query?. Looking at the FunctionQuery.java source > code, there's a comment that says "// instead of matching all docs, we > could also embed a query. the score could either ignore the subscore, or > boost it", which is giving us some hope that maybe it's possible and even > desirable to go in this direction. If you can give us some directions about > how to go about this, we may be able to do the actual implementation. > > BTW, we're using Lucene/SOLR trunk. > > Thanks a lot for your help. > Carlos > > [1]: http://wiki.apache.org/solr/FunctionQuery#Sort_By_Function >
