This improvement is built on top of the Synonym Query Style feature and brings the possibility of boosting synonym queries using the payload associated.
It introduces two new modalities for the Synonym Query Style :
PICK_BEST_BOOST_BY_PAYLOAD -> build a Disjunction query with the clauses boosted by payload
AS_DISTINCT_TERMS_BOOST_BY_PAYLOAD -> build a Boolean query with the clauses boosted by payload
This new synonym query styles will assume payloads are available so they must be used in conjunction with a token filter able to produce payloads.
An synonym.txt example could be :
- Synonyms used by Payload Boost
tiger => tiger|1.0, Big_Cat|0.8, Shere_Khan|0.9
leopard => leopard, Big_Cat|0.8, Bagheera|0.9
lion => lion|1.0, panthera leo|0.99, Simba|0.8
snow_leopard => panthera uncia|0.99, snow leopard|1.0
A simple token filter to populate the payloads from such synonym.txt is :
<filter class="solr.DelimitedPayloadTokenFilterFactory" encoder="float" delimiter="|"/>