Deadlocks. Understanding and Troubleshooting - Denis Reznik

I would not reveal a secret if I said that the deadlock is not fun at all. The definition of deadlock is straightforward and quite clear: This is an exceptional situation when two concurrent queries request the same resources but in a different order. Unfortunately, in real life, deadlocks often are more complex and unobvious. One of the rules, which I always keep in mind, sounds: "You can not design a database, in which deadlock can't happen". So, we should deal with them. The algorithm is simple: 1. Catch the deadlock 2. Find the root cause 3. Design and implement a solution. In practice, these steps can be tricky and may require different types of analysis. In this session, we will remind the concepts of locks and transaction isolation levels, and then look at ten various deadlocks scenarios and find the root cause of the deadlocks. After that, you will see how easy solution searching could be if we did a good job on the previous step.

Watch the session recording from PASS Summit 2020. For updates on the future of PASS, SQLSaturdays and PASS Summit opt in here: http://www.red-gate.com/pass