SQL Server index rebuid online and blocking scenario


 

A couple of months ago, I experienced a problem about index rebuild online operation on SQL Server. In short, the operation was supposed to be online and to never block concurrent queries. But in fact, it was not the case (or to be more precise, it was partially the case) and to make the scenario more complex, we experienced different behaviors regarding the context. Let’s start the story with the initial context: in my company, we usually go through continuous deployment including SQL modification scripts and because we usually rely on daily pipeline, we must ensure related SQL operations are