[FIXED] How can I write SQL query in JPA repository with Spring Boot?

Issue

I'm doing a spring boot experiment and using MySQL.

For example, if I have a list of users, but I want to get the specified names, how can I write the SQL query that only indicates this situation?

This is my model class :

@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Entity
@Table(name="users")
public class User {
    
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    public long id;
    
    @Column(name="first_name")
    public String name;
    
    @Column (name="last_name")
    public String last_name;
}

This is my JPA interface :

public interface CommentRepository extends JpaRepository<User , Long >{

  // All C.R.U.D database methods
}

Finally, my controller area is as below :

@RestController
@RequestMapping(path="/api/v1/users")
public class CommentController {
    
    @Autowired
    CommentRepository repository ;
    
    @GetMapping(path="/list")
    public List<User> users() {
        
        return repository.findAll();
    }  
}

Maybe you didn't understand my problem, I just want to write a customizable query of my own.

For example, I want to pull the data with the method I designed, while I normally pull the data by numbers with the find by id method.

Solution

You can either use methods that will be translated into queries or write your queries in the @Query annotation.

Please read the docs: https://docs.spring.io/spring-data/jpa/docs/current/reference/html/#repositories

Answered By - Simon Martinelli
Answer Checked By - Terry (JavaFixing Volunteer)