Hi all,
I've noticed that this very question was asked a number of times and always closed without an answer.
I am new to Elasticsearch and I've managed to GROUP the hits of a query BY multiple fields, which is good news. Last step I am missing is: inside your aggregated bucket you can then avg, sum, and all sorts of mathematical aggregations.
But I need to come out with a String that is the string concatenation of all the values in the bucket for a certain field. I guess I am literally searching for a GROUP_CONCAT()-like functionality.
Any luck?