As of SQL Server 2019, there is only one ordered set function:
STRING_AGG(). I like
STRING_AGG()a lot, especially because it means my days of needing to explain the
FOR XML PATHtrick to concatenate values together in SQL Server are numbered.
STRING_AGG()is interesting in that we categorize it as a window function and yet it violates my first rule of window functions: there isn’t an
OVER()clause. Instead, it accepts but does not require a
WITHIN GROUP()clause. Let’s see it in action.
Click through for a look at that, as well as a little hint that maybe we’ve seen ordered set functions before in a different guise.