Solr Subquery Stage
The Solr Subquery query pipeline stage is used to query external collections. The Solr Subquery stage runs a query and adds the results to the pipeline Request object. The query must return results in JSON format, so that they can be added to the query pipeline.
This stage supports asynchronous processing.
When entering configuration values in the UI, use unescaped characters, such as
\t for the tab character. When entering configuration values in the API, use escaped characters, such as
\\t for the tab character.