July 15, Apache Lucene project released Java-based search software “Apache Lucene 8.6.0” and Lucene-based server “Apache Solr 8.6.0”.
Apache Lucene project is made up of Lucene Core, and Lucene-Core-based full-text search server Solr. Lucene Core and Solr are developed and released in step with one another. Apache Lucene 8.0 and Solr 8.6 are the latest releases of the version 8 series, which came out in the spring of 2019.
Lucene has introduced the new IndexWriter merge-on-commit feature, which merges small segments on commit. It can be used for timeout configuration, improving search performance, and more. It also adds the new grouping-by-range function based on DoubleValueSource and LongValueSource
It includes API changes in SimpleFSDireectory, IndexWriterConfig, and MergeScheduler. Some of the queries bring better performance, and streaming expression and Query DSL have are improved. Solr introduces Cross Collection Join query. This method can be executed even in cases where node is overlapped or shared. Also, the package manager supports cluster (CoreContainer) level plugins. Admin UI has been enhanced with a new panel with security information in the dashboard.
Apache Lucene and Solr 8.6 are available for download from the Apache Lucene project website.