Joining in Lucene
In the real world data isn’t flat. Data is often modelled into complex models. Lucene is document oriented and doesn’t support relations natively. The only way you could index this data is by de-normalizing the relations in a document with many fields and execute subsequent queries. Subsequent queries can be expensive and data gets duplicated. This isn’t always ideal. Recently Solr and Lucene provide features that allow you to join and group. You can join and group on fields across documents and still have the power of Lucene’s awesome free text search. In the presentation we’ll dive into Lucene's joining features, the advantages and disadvantages and how joining can be used.
Watch the video of Martijn van Groningen's talk here.