Pessimistic concurrency control vs Optimistic concurrency control in Database Systems Explained

In this video, I discuss the different concurrency control at database transactions, specifically the pessimistic vs optimistic concurrency control. and the pros and cons of each.    0:00 Intro 3:00 concurrency Control 5:30 Pessimistic concurrency Control 9:20 Optimistic concurrency Control  Resources  https://en.wikipedia.org/wiki/Optimistic_concurrency_control https://www.baeldung.com/java-jpa-transaction-locks https://docs.oracle.com/javaee/7/api/javax/persistence/OptimisticLockException.html https://en.wikipedia.org/wiki/Time-of-check_to_time-of-use https://www.2ndquadrant.com/en/blog/postgresql-anti-patterns-read-modify-write-cycles/