ByThorben JanssenThe Java Persistence Query Language (JPQL) is the most common way to query data from a database with JPA. It enables you to reuse your mapping definitions and is easier to use than SQL. But it supports only a small subset of the SQL standard, and it also provides no support for database-specific features. So…
ByThorben JanssenWhen using Spring Data JPA, you are used to derived and custom queries that return the result in your preferred format. A typical example is a DTO projection, which is the most efficient one for read-only operations. To use it in a derived or custom JPQL query, you only need to change the return type…
ByThorben JanssenHibernate Envers is a popular library that automates the creation of an audit log. As I’ve shown in previous articles, it logs all write operations performed using your entity classes in an audit log and provides a flexible API to query data from that log. Based on these articles, I got recently asked if Hibernate…
ByThorben JanssenAs shown in my previous post, Hibernate offers several APIs to query data from the database. If you want to define your query dynamically at runtime, you can use JPA’s Criteria API. In the past, Hibernate also offered its own proprietary Criteria API. It has been deprecated in Hibernate 5, and you should avoid it…
ByThorben JanssenThe size of a result set has a huge impact on the performance of a query, the burden it puts on your Java application, and the user experience your UI provides. It’s a general best practice to split huge result sets into multiple parts presented on separate pages. This process is called pagination. The most…