jpa groupby

JPA (Java Persistence API) is a specific[ati](https://geek.csdn.net/educolumn/150d7073277950db5f09620704e791cf?spm=1055.2569.3001.10083)on for managing rel[ati](https://geek.csdn.net/educolumn/150d7073277950db5f09620704e791cf?spm=1055.2569.3001.10083)onal data in Java applic[ati](https://geek.csdn.net/educolumn/150d7073277950db5f09620704e791cf?spm=1055.2569.3001.10083)ons. It provides a set of interfaces and classes for object-rel[ati](https://geek.csdn.net/educolumn/150d7073277950db5f09620704e791cf?spm=1055.2569.3001.10083)onal mapping (ORM) and performing database oper[ati](https://geek.csdn.net/educolumn/150d7073277950db5f09620704e791cf?spm=1055.2569.3001.10083)ons. When it comes to grouping data in JPA, you can use the GROUP BY clause in JPQL (Java Persistence Query Language) queries. The GROUP BY clause is used to group the results based on one or more properties or expressions. Here's an example of using GROUP BY in JPA: ```java TypedQuery<Object[]> query = entityManager.createQuery( "SELECT e.category, COUNT(e) FROM Entity e GROUP BY e.category", Object[].class List<Object[]> results = query.getResultList(); for (Object[] re ```