Release date: 28 February 2019 Component versions:
Solr 7.5ZooKeeper 3.4.13Spark 2.3.1Jetty 9.4.11.v20180605Ignite 2.3.0
More information about support dates can be found at Lucidworks Fusion Product Lifecycle.

New features

  • Smarter relevancy with query rewriting Query rewriting turns ineffective queries into more relevant results by automatically correcting misspelled terms, expanding queries to include synonyms, boosting known phrases, and applying your own business rules. 4.2.0 ties together existing query rewriting features and adds new features to make query rewriting easier to configure:
  • Refine the final search results with response rewriting Similar to query rewriting, response rewriting can apply machine learning, business rules, or other criteria to Solr’s response, refining the final set of search results before Fusion sends them to the search application. Response rewriting can be performed using rules and a set of new query pipeline stages that fall into two categories:
  • More Natural Language Processing (NLP) power in pipelines This release includes a new NLP Annotator index stage and query stage that leverage the popular John Snow NLP library for Spark, introducing these new NLP features in addition to the existing Named Entity Extraction (NER) functionality:
See the Fusion Server 4.2.0 release notes and the App Studio 4.2.0 release notes for other changes.

Improvements

  • Experiments can now be configured as Plan an Experiment, by selecting the new Automatically Adjust Weights Between Variants option when Set Up an Experiment using a Query Profile.
  • A Part-of-Speech (POS) model is now available in the blob store by default, as en-pos-maxent.bin, for use by the Phrase Extraction job.

Known issues

  • In Underperforming Query Rewriting and Misspelling Detection, new or modified query rewrites cannot be saved when any of their values include trailing or leading whitespace. Remove any trailing or leading whitespace to save the query rewrite.
  • The Query Rewriting UI’s search feature joins multiple search terms using OR instead of AND. For example, searching for a rule called “Test 1” returns “Test 1”, “Test 2”, and “1 Rule”.
  • The Query Rewriting UI’s search feature may return a Problem with underlying storage if your query is *:* followed by an additional query term. This is an invalid query; use only *:* to search for all query rewrites.
  • In Underperforming Query Rewriting, job-generated query improvements do not preserve the original query’s uppercase and lowercase characters. For example, an underperforming query containing “brandX” may be rewritten to contain “brandx”. You may need to manually modify the query improvements to preserve the correct cases.
  • After selecting multiple business rules where some rules have tags, adding more tags to the selected rules deletes their existing tags. To work around this, add tags to individual rules instead of adding them in bulk.
See also the Fusion Server 4.2.0 known issues.