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What is Hibernate?
Hibernate is ORM framework and it works as one of the ORM provider in case of JPA application. Hibernate is used to map Java objects to relational database table row and vice versa.
It hides JDBC complexity from programmers and generates SQL on fly for the operation specified by call made from Java program.
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What is use of Hibernate?
Hibernate is famous and one of the most used ORM framework in Java. It helps programmers to write Java code for interacting with the database. Hibernate is also independent from the database which means you can switch your database backend.
Hibernate is used to make persistence layer of application.
Check: When should you use Hibernate?