Когда нам следует использовать аннотацию @Transactional? ⇐ JAVA

[Гость]

Я хотел знать, когда нам следует использовать

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@Transactional

in Spring Boot Services.
Since JpaRepository's

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save()

method is annotated with

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@Tranasactional

is it required for me to add that annotation in my service method?
I've seen a couple of articles saying that if there is only a repository being used inside your service method (like in the below scenario) then it's not required to put

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@Transactional

on the service method as

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save()

is already annotated with

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@Transactional

. Is it true?

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class EmployeeService {
@Autowired
EmployeeRepository repo;

@Transactional //(Is it required here?)
public void saveEmployee(Employee employee) {
repo.save(employee)
}
}

Should it be used in this below case on method

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getStudentsWithNameStartsWithAndGradeLessThan()

since we are using more than one Repository?

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@Getter
@Setter
@Entity
@Table(name = "student")
public class Student {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id", nullable = false)
private Long id;

@Column(name = "name")
private String name;

@Column(name = "average_grade")
private Short averageGrade;
}

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public interface StudentRepository extends JpaRepository {
Set findByAverageGradeLessThan(Short averageGrade);
Set findByNameStartsWithIgnoreCase(String name);
}

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@Service
public class StudentService {

private final StudentRepository studentRepository;

public StudentService(StudentRepository studentRepository) {
this.studentRepository = studentRepository;
}

@Transactional //(Is it required here?)
public Set getStudentsWithNameStartsWithAndGradeLessThan(String prefix, Short averageGrade) {

Set students = studentRepository.findByNameStartsWithIgnoreCase(prefix);
students.retainAll(studentRepository.findByAverageGradeLessThan(averageGrade));
return students;

}
}

Источник: https://stackoverflow.com/questions/781 ... annotation