Finding The First Non-NULL Value In A Window

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.

Related Posts

Defending ANSI-89 Syntax

Allan Hirt prefers ANSI-89 join syntax: Pedro Lopes who is now on the SQL Server dev team wrote the blog post “T-SQL Misconceptions – JOIN ON vs. WHERE” which does a good job of explaining the “it depends” around the newer style of joins. Why link this article? Microsoft deprecated the OUTER JOIN operators in SQL Server […]

Read More

Pivoting Performance Counter Data

Dave Bland shows how you can build a dynamic pivot to see performance counter data over a stretch of time: The next step is to write the code to capture the counter values and insert the data it the temporary table created above.  Because we need to capture the values over a period of time, […]

Read More

Categories

August 2018
MTWTFSS
« Jul Sep »
 12345
6789101112
13141516171819
20212223242526
2728293031