Deadlocks - Understanding and Troubleshooting

Explore the intricacies of deadlocks in database systems through this comprehensive one-hour conference talk from PASS Data Community Summit. Delve into the fundamental concepts of locks and transaction isolation levels before examining ten diverse deadlock scenarios and their root causes. Learn how to effectively catch deadlocks, identify their origins, and design appropriate solutions. Gain insights into various lock types, including shared, exclusive, update, and intent locks, as well as concepts like lock escalation, non-repeatable reads, phantom records, and different isolation levels. Discover the three rules of deadlocks and strategies to avoid them, equipping yourself with essential knowledge for troubleshooting and optimizing database performance.

Intro
Agenda
DEADLOCK!
Lock Types - Shared
Lock Types - Exclusive
NON-REPEATABLE READS
Merge Join
Lock Types - Update
Lock Escalation
Lock Types – Intent locks
PHANTOM RECORDS
SERIALIZABLE
READ COMMITTED SNAPSHOT
READ UNCOMMITTED (NOLOCK)
Three Rules of Deadlocks
How to Avoid?