Siren Vanguard is a completely new software product replacing its predecessor, Siren Join. It provides improved performance and scalability, and a platform on which we can develop more advanced features. Vanguard is a plugin for Elasticsearch that adds join capabilities across indices. Currently one type of join is implemented which we call Search Join, but our objective is to add more type of joins in the future.  Read our blog on Vanguard.

Using the Vanguard plugin

The Search Join is basically a (left) semi-join between two set of documents based on a common attribute, where the result only contains the attributes of one of the joined set of documents. This join is used to filter one document set, based on a second document set - hence its name. It is equivalent to the EXISTS() operator in SQL The Search Join supports joins on both numerical and textual fields, but the joined attributes must be of the same type. You can also freely combine and nest multiple Search Joins using boolean operators (conjunction, disjunction, negation) to create complex query plans. It is fully integrated with the Elasticsearch API and is compatible with distributed environments.


Vanguard is free to use on any number of nodes for development and test purposes only. For commercial purposes get your free 1 node licence or contact us for a quote.

Download the latest Vanguard

Looking for Elasticsearch 2.x compatibility? Check out our Elasticsearch 2.x compatible plugin, Siren Join.