SQL, How to Concatenate results?

Question

I currently have a SQL query that returns a number of fields. I need one f the fields to be effectively a sub query sub that.

The Problem in detail:

Answer 1

In my opinion, if you are using SQL Server 2017 or later, using STRING_AGG( ... ) is the best solution:

More at:

https://stackoverflow.com/a/42778050/1260488