Question

I’m using Apache Solr and querying an index with a schema that has a text field PostBody, a integer Userid field, and a trie based datetime field MostRecentActivityDate.

I’m attempting to apply query-time boosting to my select query such that more recent posts are boosted by some factor to assist in scoring. My values for this are in attempts to have a timescale of days rather than years as in many online date boosting examples.

The following two queries produce different results, the only thing being different in them is where the “code” for the boosting is actually placed (i.e. prior to or after the field conditionals themselves). In my testing I’ve also noticed that they both produce different results from when there is no {} boosting code, so its not as if in one case its being ignored.

Is anyone able to explain why they would produce different results? Thanks!

{!boost%20b=recip(ms(NOW,MostRecentActivityDate),1.16e-7,1,1)} (PostBody:"timmy is great and that is a fact") AND !Userid=2

Vs.

(PostBody:"timmy is great and that is a fact") AND !Userid=2 {!boost%20b=recip(ms(NOW,MostRecentActivityDate),1.16e-7,1,1)}

Answer 1

Since this will be very specific to your data, the best way to figure out what is happening, is to turn on query Debugging – via the debugQuery=on parameter of your search. Here are two links that help explain the debug output.

• Debugging Search Applications Relevance – Explanations
• Why does id:archangel come before id:hawkgirl when querying for “wings”