ByThorben JanssenIf you just want to update 1 or 2 entities, you can simply fetch them from the database and perform the update operation on it. But what about updating hundreds of entities? You can, of course, use the standard approach and load and update each of these entities. But that is often too slow because…
ByThorben JanssenJPA supports a set of database functions which you can use to perform small operations and transformations within a query. This is often easier and faster than doing it in the Java code. But how do you call functions which are not supported by the JPA standard, like database-specific ones or the custom functions implemented…
ByThorben JanssenI’m currently recording the Hibernate Performance Tuning Online Training and today I want to share the lecture about Hibernate’s 1st level cache with you. Hibernate activates the 1st level cache by default and uses it to optimize the performance of your application if you don’t prevent it. OK, you probably wonder why you should prevent Hibernate from using the cache…
ByThorben JanssenLoading related entities with JPA and Hibernate is a comfortable feature that is also the most common reason for performance issues. In most applications you can find one of these two issues: related entities are eagerly loaded, even if they are not needed or related entities are lazily loaded which creates n+1 select issues if…
ByThorben JanssenDefining a static named query via the @NamedQuery annotation is the most common way in JPA. It has the main advantage that the persistence provider can compile and validate the query at start-up time. But you also have to define the query statically at compile time. OK, you can still define a dynamic query at runtime but how do you…