MariaDB 10.3 supports database sequences
Introduction Traditionally, both MySQL and MariaDB relied on AUTO_INCREMENT columns to generate an IDENTITY Primary Key. Although IDENTITY columns are very efficient in generating the Primary Key value, when it comes to using JPA and Hibernate, the IDENTITY generator prevents us from using JDBC batch inserts. To automatically enroll multiple INSERT, UPDATE or DELETE statements, Hibernate requires delaying the SQL statement until the Persistence Context is flushed. This works very well for the SEQUENCE identifier since the entity identifier can be fetched prior to executing the INSERT statement. However, for IDENTITY columns,… Read More
How to improve statement caching efficiency with IN clause parameter padding
Introduction Recently, I stumbled on the following Twitter thread: This jOOQ feature is indeed really useful since it reduces the number of SQL statements that have to be generated when varying the IN clause parameters dynamically. Starting with Hibernate ORM 5.2.18, it’s now possible to use IN clause parameter padding so that you can improve SQL Statement Caching efficiency. In this article, I’m going to explain how this new mechanism works and why you should definitely consider it when using a relational database system that supports Execution Plan caching.
How to synchronize bidirectional entity associations with JPA and Hibernate
Introduction While answering this StackOverflow question, I realized that it’s a good idea to summarize how various bidirectional associations should be synchronized when using JPA and Hibernate. Therefore, in this article, you are going to learn how and also why you should always synchronize both sides of an entity relationship, no matter if it’s @OneToMany, @OneToOne or @ManyToMany.
How to avoid the Hibernate Query Cache N+1 issue
Introduction I recently answered this question on the Hibernate forum, and since it’s a very good one, I decided to turn it into an article. In this post, we will describe how the N+1 query issue is generated when using the second-level Hibernate Query Cache.
How to map an immutable entity with JPA and Hibernate
Introduction In this article, you are going to find out how to map an immutable entity when using JPA and Hibernate. If your Domain Model requires that a given entity should not be modified by the data access logic, Hibernate can enforce this requirement if the entity is marked with the @Immutable annotation.
PostgreSQL SERIAL or IDENTITY column and Hibernate IDENTITY generator
Introduction When using PostgreSQL, it’s tempting to use a SERIAL or BIGSERIAL column type to auto-increment Primary Keys. PostgreSQL 10 also added support for IDENTITY, which behaves in the same way as the legacy SERIAL or BIGSERIAL type. This article will show you that SERIAL, BIGSERIAL, and IDENTITY are not a very good idea when using JPA and Hibernate.
How to customize the Hypersistence Utils JSON Serializer
Introduction The Hypersistence Utils open-source project allows you to map JSON, ARRAY, and PostgreSQL ENUM types and provides a simple way of adding immutable Hibernate Types. After adding support for customizing the Jackson ObjectMapper, the next most-wanted issue was to provide a way to customize the JSON serializing mechanism. In this article, you are going to see how you can customize the JSON serializer used by the JSON Types.
How to use a JVM or database auto-generated UUID identifier with JPA and Hibernate
Introduction In this article, we are going to see how to use a UUID entity identifier that is auto-generated by Hibernate either in the JVM or using database-specific UUID functions. Our Post entity looks as follows: The Post entity has a UUID identifier and a title. Now, let’s see how we can map the Post entity so that the UUID identifier be auto-generated for us.
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.
