Redis - Why details are saving both as HASH and SET using Spring Data Redis? - spring

Question

I am new to Redis and developing Spring Boot + Spring Data Redis example. I am using CrudRepository, Example and ExampleMatchers API to do the searching from the Redis Key value store DB.
Now when I simply run my code, I saw that persons data saved as SET and HASH as well. Is this correct ? What's the use of saving the Person details both as SET and HASH
Showing all my code
public enum Gender {
MALE, FEMALE {
#Override
public String toString() {
return "Superwoman";
}
}
}
Species.java
#Builder
#Data
#AllArgsConstructor
#NoArgsConstructor
public class Species {
#Indexed
private String name;
}
Person.java
#Data
#Builder
#AllArgsConstructor
#NoArgsConstructor
#RedisHash("persons")
public class Person {
#Id
private String id;
#Indexed
private String firstname;
private String lastname;
#Indexed
private Gender gender;
private List<String> nicknames;
#Indexed
private Integer age;
private Map<String, String> physicalAttributes;
#Reference
private Person relative;
private Species species;
}
PersonRepository.java
public interface PersonRepository extends CrudRepository<Person, String>, QueryByExampleExecutor<Person> {
}
RedisExampleDemoApplication.java
#SpringBootApplication
public class RedisExampleDemoApplication implements CommandLineRunner{
RedisMappingContext mappingContext = new RedisMappingContext();
ExampleQueryMapper mapper = new ExampleQueryMapper(mappingContext, new PathIndexResolver(mappingContext));
#Autowired
private PersonRepository personRepository;
public static void main(String[] args) {
SpringApplication.run(RedisExampleDemoApplication.class, args);
}
#Override
public void run(String... args) throws Exception {
Person person = Person.builder().firstname("Walter").gender(Gender.MALE).age(50).build();
Person person1 = Person.builder().firstname("Savani").gender(Gender.FEMALE).age(35).build();
personRepository.save(person);
personRepository.save(person1);
// [firstname:Walter, gender:MALE, age:50]
RedisOperationChain operationChain = mapper.getMappedExample(Example.of(person, ExampleMatcher.matchingAny()));
System.out.println(operationChain.getOrSismember());
System.out.println("----------------------------------------------");
Person p = Person.builder().lastname("Foo").build();
RedisOperationChain roc = mapper.getMappedExample(Example.of(p));
System.out.println(" == "+roc.getOrSismember());
System.out.println("-- "+roc.getSismember());
}
}

Answer 1

May be it is late to answer now , the reason that SET is visible is because of the secondary Index. I.e in your example First name is annotated as Indexed. Redis consider this as secondary index which is default a SET.