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In Hibernate, an orphan entity refers to a child entity that has been disassociated from its parent. If these orphan entities are not explicitly removed, they remain in the database and result in unwanted data. The orphanRemoval = true attribute on the mapping annotation on parent entity automatically removes the child entities from the database …
Learn to create and inject an in-memory DataSource that can be used to mock J2EE container provided JNDI DataSource without running a server.
Learn to execute bulk SQL INSERT and UPDATE statements using Hibernate / JPA batch processing, and to configure session-specific batch sizes.
Hibernate provides support for executing the stored procedures and capturing their outputs using StoredProcedureQuery and ProcedureCall APIs.
Learn to use the Hibernate aggregate functions used to query a calculated value for a field among all entities matching the given criteria.
Learn to configure full text and query index-based searches in Hibernate using backends like Lucene, Elasticsearch or OpenSearch.
Learn to use Hibernate Interceptor for getting callbacks for persistence events and register it with Session and SessionFactory interfaces.
Learn to implement and test the pagination functionality in hibernate using the HQL setFirstResult(), setMaxResults() and ScrollableResults.
Learn to sort the entities fetched from the database using hibernate HQL, native SQL, Criteria queries and Comparator interface.
Learn to delete a single entity or a list of entities matching some criteria using hibernate native APIs and Jakarta persistence APIs.
Learn to use the Hibernate’s native event callback mechanism and annotation based callback events from the new Jakarta persistence API.
Learn to initialize the EnitytManager using the XML configuration and the programmatic configuration in hibernate 6 and Jakarta persistence.
In Spring MVC and Hibernate configuration example, learn to create form-based CRUD application that validates and persists data into database.
Learn to use hibernate initialize() method and enable_lazy_load_no_trans property to force initialization of proxy entity or collection.
Learn to execute SQL stored procedures with the help of @NamedStoredProcedureQuery annotation from Jakarta persistence API that helps in specifying the name of a stored procedure, its parameters, and its result type. 1. Project Setup The support for executing stored procedures using @NamedStoredProcedureQuery has been added in JPA 2.1. So …
Learn the drawbacks and benefits of using the annotations configuration over XML files to better know when to apply which format.
Hibernate fetches data from the database either in eager or lazy mode. Lazy loading refers to a strategy when data is loaded on demand.
Learn JPA Cascade Types and how they are related to Hibernate Cascade Types. Learn how to control the orphan removal with an example.
Hibernate merge() does exactly the opposite of what refresh() does i.e. causing the updates to database with values from the detached entity.
Learn the difference between get() vs load() methods that are used to fetch entity by id from the database using Hibernate.
Learn why it is important to implement hashCode() and equals() methods in hibernate entity classes. How does it affect different Sessions.
Learn to configure C3P0 connection pooling with Hibernate 6. Learn how to enforce c3p0 over other connection polls and debug connection leaks.
Learn to connect to an in-memory database (such as H2 or Hsqldb) from the JUnit 5 unit tests. This will help in writing tests that do not depend on a live database connection.
Learn to bootstrap SessionFactory with StandardServiceRegistryBuilder, StandardServiceRegistry and Metadata in Hibernate versions 5 and 6.
Learn to store and fetch large objects such as images, videos and other documents. Learn to mapping objects to LOB, CLOB and other types
Learn to use the EntityManager’s getReference() and find() usages and differences, their behavior when the primary identifies does not exist.
Learn the difference between natural id and primary id, @NaturalId annotation and various APIs to load persistent and proxy entities.
Learn to create, group and execute named HQL and named native SQL queries in Hibernate using @NamedQuery and @NamedNativeQuery annotations.
The hibernate second-level cache is separate from the first-level cache and is available to be used globally in SessionFactory scope.
The first level cache (enabled by default) helps Hibernate to reduce the number of queries made to the database to improve the performance.
Learn to insert an object into the database using hibernate’s Session interface, JPA’s EntityManager and HQL Query interface with examples.
Step by step hibernate hello world example with maven and eclipse. Learn to create, configure and store hibernate 5 entities in the database.
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