The analysis of blocking in SQL Server can be hard if the SQL Server instance has a high number of active connections. This analysis becomes complicated because busy instances could have more than one blocking connection, meaning that we could have more than just one blocking chain. For every group of blocked connections, we could also have more than two connections being blocked.

This article will show you how the analysis of blocking connections could be simplified by using a proc, sp_who4, developed by the author of this article. The only purpose of the procedure is the the simplification