Bert Wagner shows off the FIRST_VALUE window function and walks us through a case it struggles with:
The SQL Server FIRST_VALUE function makes it easy to return the “first value in an ordered set of values.”
The problem is that if that first value happens to be a NULL, there is no easy, built-in way to skip it.
While a UserVoice item exists to add the ability to ignore nulls (go vote!), today, we’re going accomplish that end result with some alternative queries.
Click through for the demo, as well as a video version of the post.