I have a use case where i want to update the document without knowing its index. Currently i am querying by id and getting the index and then updating (2 operation). Update By Query API seems to perform this use case in single operation. But i am just skeptical because as per the elasticsearch documentation,
When you submit an update by query request, Elasticsearch gets a snapshot of the data stream or index when it begins processing the request and updates matching documents using internal versioning.
As there will be a lot of updates individually, just want to know whether there will be a performance overhead when using _update_by_query for updating single document than getting and update using _update api.
Thanks in Advance.