Clik here to view.
Hibernate CascadeType.LOCK gotchas
Introduction Having introduced Hibernate explicit locking support, as well as Cascade Types, it’s time to analyze the CascadeType.LOCK behavior. A Hibernate lock request triggers an internal LockEvent....
View ArticleClik here to view.
A beginner’s guide to read and write skew phenomena
Introduction In my article about ACID and database transactions, I introduced the three phenomena described by the SQL standard: dirty read non-repeatable read phantom read While these are good to...
View ArticleClik here to view.
MySQL metadata locking and database transaction ending
Introduction As previously explained, every SQL statement must be executed in the context of a database transaction. For modifying statements (e.g. INSERT, UPDATE, DELETE), row-level locks must be...
View ArticleClik here to view.
A beginner’s guide to the Phantom Read anomaly, and how it differs between...
Introduction Unlike SQL Server which, by default, relies on the 2PL (Two-Phase Locking) to implement the SQL standard isolation levels, Oracle, PostgreSQL, and MySQL InnoDB engine use MVCC...
View ArticleClik here to view.
How does database pessimistic locking interact with INSERT, UPDATE, and...
Introduction Relational database systems employ various Concurrency Control mechanisms to provide transactions with ACID property guarantees. While isolation levels are one way of choosing a given...
View ArticleClik here to view.
How does a relational database work
Introduction While doing my High-Performance Java Persistence training, I came to realize that it’s worth explaining how a relational database works, as otherwise, it is very difficult to grasp many...
View ArticleA beginner’s guide to Linearizability
Introduction Linearizability is a lesser-known, yet omnipresent property of a data registry in the context of read and write operations that might happen concurrently. This article aims to explain what...
View ArticleA beginner’s guide to Serializability
Introduction In this article, we are going to see what Serializability means and what guarantees does it offer. Relational database systems provide a Serializable isolation level that’s supposed to...
View ArticleThe race condition that led to Flexcoin bankruptcy
Introduction It’s hard to imagine that a race condition bug could lead to the bankruptcy of a given online service, isn’t it? In this article, I’m going to show you how a race condition led to the...
View ArticleSpring Transaction Best Practices
Introduction In this article, I’m going to show you various Spring Transaction Best Practices that can help you achieve the data integrity guarantees required by the underlying business requirements....
View Article