Когда нам следует использовать аннотацию @Tranasactional? ⇐ JAVA

[Гость]

I wanted to know when exactly we should use

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@Tranasactional

in Spring Boot Services.
Since JpaRepository's

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save()

method is annotated with

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@Tranasactional

is it really required for me to add that annotation in my service method?
I've seen couple of articles saying that if there is only 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 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;
}

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

@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