User Guide for Siren Federate

Join Query

The join filter enables the filtering of one set of documents (the target) with another one (the source) based on shared field values. It accepts the following parameters:

type
The type of the join algorithm to use. Valid values are either BROADCAST_JOIN, HASH_JOIN or MERGE_JOIN. If this parameter is not specified, the query planner will try to automatically select the optimal one.
indices
The index names that will be joined with the source indices. Defaults to all indices.
types
The index types that will be joined with the source indices. Defaults to all types.
on
An array specifying the field paths for join keys in both source and target indices. Both fields must have the same datatype with the parameter doc_values set to true. It is not recommended to join fields based on text datatype.
request
The search request that will be used to compute the set of documents on the source before performing the join.