The Java Persistence API (JPA) is a Java specification for accessing, persisting and managing data between Java objects/classes and a relational database. JPA was defined as part of the EJB 3.0 specification as a replacement for the EJB 2 CMP Entity Beans specification. JPA is now considered the standard industry approach for Object to Relational Mapping (ORM) in the Java Industry.
The current version of the JPA specification is JPA 2.1 (JSR 338), released on 22 April 2013. It includes several improvements, such as type-converter and stored procedures.
Spring Data JPA Update @Query not updating? While this question is about Spring Data JPA the underlying problem is about understanding the 1st level cache of JPA. See also the many duplicates pointing to that question.Source Info