Hibernate database catalog multitenancy
Introduction As I explained in this article, multitenancy is an architectural pattern which allows you to isolate customers even if they are using the same hardware or software components. There are multiple ways you can achieve multitenancy, and in this article, we are going to see how you can implement a multitenancy architecture using the database catalog as the unit of isolation.
A beginner’s guide to database multitenancy
Introduction In software terminology, multitenancy is an architectural pattern that allows you to isolate customers even if they are using the same hardware or software components. Multitenancy has become even more attractive with the widespread adoption of cloud computing. A relational database system provides a hierarchy structure of objects which, typically, looks like this: catalog -> schema -> table. In this article, we are going to see how we can use each of these database object structures to accommodate a multitenancy architecture.
A beginner’s guide to Phantom Read anomaly
Introduction Database transactions are defined by the four properties known as ACID. The Isolation Level (I in ACID) allows you to trade off data integrity for performance. The weaker the isolation level, the more anomalies can occur, and in this article, we are going to describe the Phantom Read phenomenon.
A beginner’s guide to Non-Repeatable Read anomaly
Introduction Database transactions are defined by the four properties known as ACID. The Isolation Level (I in ACID) allows you to trade off data integrity for performance. The weaker the isolation level, the more anomalies can occur, and in this article, we are going to describe the Non-Repeatable Read phenomenon.
A beginner’s guide to Dirty Read anomaly
Introduction Database transactions are defined by the four properties known as ACID. The Isolation Level (I in ACID) allows you to trade off data integrity for performance. The weaker the isolation level, the more anomalies can occur, and in this article, we are going to describe the Dirty Read phenomenon.
PostgreSQL reWriteBatchedInserts configuration property
Introduction The PostgreSQL JDBC Driver has been adding a lot of very useful optimizations, and one of the lesser-known ones is the reWriteBatchedInserts configuration property. In this article, you will see how the reWriteBatchedInserts JDBC configuration property works in PostgreSQL, and how it allows you to rewrite INSERT statements into a multi-VALUE INSERT.
How to use database-specific or Hibernate-specific features without sacrificing portability
Introduction Like other non-functional requirements, portability is a feature. While portability is very important when working on an open-source framework that will be used in a large number of setups, for end systems, portability might not be needed at all. This article aims to explain that you don’t have to avoid database or framework-specific features if you want to achieve portability.
How does MVCC (Multi-Version Concurrency Control) work
Introduction In this article, I’m going to explain how the MVCC (Multi-Version Concurrency Control) mechanism works using PostgreSQL as a reference implementation. In Concurrency Control theory, there are two ways you can deal with conflicts: You can avoid them, by employing a pessimistic locking mechanism (e.g. Read/Write locks, Two-Phase Locking) You can allow conflicts to occur, but you need to detect them using an optimistic locking mechanism (e.g. logical clock, MVCC) Because MVCC (Multi-Version Concurrency Control) is such a prevalent Concurrency Control technique (not only in relational database systems, in this article,… Read More
How to encrypt and decrypt data with Hibernate
Introduction Today, one of my Twitter followers sent me the following StackOverflow question, and, while answering it, I realized that it definitely deserves a post of its own. In this post, I will explain how you can encrypt and decrypt data with Hibernate.
