Working with Lock Conflicts

Abstract

The whole idea of locks is to restrict access to objects or records to avoid conflicting operations to concurrently access the object or records in a safe way. That means that, sometimes, a lock cannot be granted. What happens in that case? It depends on the locks requested and the circumstances. Metadata (including explicitly requested table locks) and InnoDB locks operate with a timeout, and for some, lock cases explicit deadlock detection exists.