使用dismax时，Solr获得计算的距离

Question

I'm starting to think that what I want to do is not possible but thought I would give this a try.

I'm running Solr 3.5.

I currently have two types of search:

1. A basic spatial query which returns the calulated distance between two points in the score field.

Sample Query from my Solr logs:

?fl=*,score&sort=score+asc&start=0&q={!func}geodist()&sfield=coordinates&pt=59.2363514,18.092783&version=2

1. A dismax query which allows free text queries on a number of fields.

Sample Query from Solr log:

mm=1&d=100.0&sfield=coordinates&qf=field1^5.0+fields2^3.0&defType=edismax&version=2&fl=*,score&start=1&q=monkeyhopper&pt=59.2363514,18.0927830000&fq={!geofilt}}

I want to replace my first query with the dismax query but I really need to get the calculated distance in the response. Yes, I can calulate the distance programatically but I would prefer not having to do this as Solr has done it for me already.

I still want to be able to sort my dismax query "by relevance", distance or any other field so the score given by my boosts could be interesting for sorting but I don't need it to be returned.

Answer 1

If I understood correctly you want to have the result of a function in your Solr response. The SOLR-2444 issue is what you're looking for I guess: it allows to include in the fl parameter pseudo-fields, functions etc. The only problem is that it's been committed only on trunk, so it isn't available on the current Solr release, neither will be in the coming 3.6 release. You have to wait for the 4 release but I don't think it will take a lot of time. Maybe you can already start playing around with a snapshot of the last successful Jenkins build.

Answer 2

Pseudo-fields are now available in Solr 4+ which allow you to do just this.

http://localhost:8983/solr/collection1/browse?q=*:*&rows=1000&wt=xml&pt=37.763649,-122.24313&sfield=store&fl=dist:geodist()

For instance, this request allows me to return a field "dist" which contains the distance of each entry to the stated point.