Spring Data JPA is a powerful module within the Spring Framework that simplifies database access and provides convenient abstractions for working with relational databases. Test your understanding of Spring Data JPA with this quiz, featuring 10 multiple-choice questions (MCQs) that cover various aspects of Spring Data JPA.
a) Spring Data JPA aims to reduce the amount of boilerplate code required for common database operations.
b) Spring Data JPA aims to provide the implementation for JPA interfaces
c) Spring Data JPA is a JPA provider and implementation for JPA interfaces
d) Spring Data JPA is an ORM framework that provides an implementation for JPA interfaces
Answer:
a) Spring Data JPA aims to reduce the amount of boilerplate code required for common database operations.
Explanation:
Spring Data JPA aims to reduce the amount of boilerplate code required for common database operations and make it easier to work with relational databases.
2. Which dependency is required to use Spring Data JPA in a Spring Boot application?
a) spring-boot-starter-data-jpa
b) spring-boot-starter-web
c) spring-boot-starter-test
d) spring-boot-starter-security
Answer:
a) spring-boot-starter-data-jpa
Explanation:
To use Spring Data JPA in a Spring Boot application, you need to include the spring-boot-starter-data-jpa dependency in your project's dependencies. This starter dependency includes the necessary dependencies for working with JPA and provides auto-configuration for Spring Data JPA.
3. Which is the default JPA provider the Spring Data JPA internally uses?
a) EclipseLink
b) MyBatis
c) TopLink
d) Hibernate
Answer:
d) Hibernate
Explanation:
Spring Data JPA uses Hibernate as a default JPA provider.
4. Which annotation marks a class as an entity in JPA?
a) @EntityClass
b) @JPAEntity
c) @Entity
d) @TableEntity
Answer:
c) @Entity
Explanation:
The @Entity annotation is used to indicate that a class is a JPA entity.
5. Which interface do we extend to create a repository in Spring Data JPA?
a) Repository
b) JpaRepository
c) JpaRepository
d) SpringRepository
Answer:
b) JpaRepository
Explanation:
JpaRepository is the interface provided by Spring Data JPA for CRUD operations.
6. What is the default implementation class of the JpaRepository interface?
a) JpaRepositoryImpl class
b) SimpleJpaRepository class
c) DeafultJpaRepository class
d) SimpleCrudRepository class
Answer:
b) SimpleJpaRepository class
Explanation:
The default implementation class of the JpaRepository interface is SimpleJpaRepository. This class is provided by Spring Data JPA and serves as the default implementation for performing CRUD (Create, Read, Update, Delete) operations on JPA entities.
7. How can you define a derived query in Spring Data JPA?
a) By annotating a method with @Query
b) By creating a method in the repository with a specific naming convention
c) By using the @DerivedQuery annotation
d) By creating an XML configuration
Answer:
b) By creating a method in the repository with a specific naming convention
Explanation:
Spring Data JPA allows developers to create queries simply by defining a method with a naming convention without writing the actual query.
8. Which annotation is commonly used to mark a repository interface in Spring Data JPA?
a) @Service
b) @Component
c) @Controller
d) @Repository
Answer:
d) @Repository
Explanation:
The @Repository annotation is commonly used to mark a repository interface in Spring Data JPA. It serves as a specialization of the @Component annotation and allows the Spring container to recognize and manage the repository.
9. Which annotation is used to autowire a repository into a Spring component?
a) @InjectRepository
b) @AutoInject
c) @Autowire
d) @Resource
Answer:
c) @Autowire
Explanation:
The @Autowire annotation is used to inject Spring beans, including repositories, into other components.
10. Which of the following is NOT a fetch type in JPA?
a) EAGER
b) LAZY
c) IMMEDIATE
d) BOTH
Answer:
c) IMMEDIATE
Explanation:
JPA provides two fetch types: EAGER and LAZY.
11. How do you execute a native query in Spring Data JPA?
a) @Native
b) @SQL
c) @Execute
d) @Query(nativeQuery = true)
Answer:
d) @Query(nativeQuery = true)
Explanation:
For native queries in Spring Data JPA, you use the @Query annotation and set the nativeQuery attribute to true.
12. Which of the following is NOT a valid Cascade type in JPA?
a) PERSIST
b) REMOVE
c) MERGE
d) UPDATE
Answer:
d) UPDATE
Explanation:
UPDATE is not a valid CascadeType in JPA.
13. How can you mark a field as the primary key in a JPA entity?
a) @PrimaryKey
b) @EntityKey
c) @Id
d) @Key
Answer:
c) @Id
Explanation:
The @Id annotation is used to denote a field as the primary key in a JPA entity.
14. What is the purpose of the @GeneratedValue annotation in Spring Data JPA?
a) To specify the table name for entity mapping.
b) To define the primary key column in an entity.
c) To configure the fetching strategy for related entities.
d) To automatically generate primary key values for entities.
Answer:
d) To automatically generate primary key values for entities.
Explanation:
The @GeneratedValue annotation in Spring Data JPA is used to automatically generate primary key values for entities. It works in conjunction with ʼ and specifies the strategy for generating primary key values, such as auto-increment, sequence, or UUID.
15. How can you customize the column name for a field in a JPA entity?
a) @Column(name="custom_name")
b) @FieldName("custom_name")
c) @TableColumn("custom_name")
d) @DatabaseColumn("custom_name")
Answer:
a) @Column(name="custom_name")
Explanation:
The @Column annotation allows you to specify the details of the column to which an entity field is mapped, including customizing the column name.
16. Which annotation is used to specify a custom query in Spring Data JPA?
a) @CustomQuery
b) @JPAQuery
c) @Query
d) @ExecuteQuery
Answer:
c) @Query
Explanation:
The @Query annotation is used to define custom queries in Spring Data JPA.
17. Which annotation is used to create a Named JPQL query?
a) @NamedQuery
b) @NamedJPQLQuery
c) @NamedNativeQuery
d) SQLQuery
Answer:
a) @NamedQuery
Explanation:
The @NamedQuery annotation is used to define a named query in a JPA entity class. It associates a specific name with a JPQL query string, allowing you to refer to and execute the query by its name instead of writing the entire query string every time.
18. How can you indicate a Many-To-One relationship in JPA?
a) @ManyToOne
b) @OneToMany
c) @ManyToMany
d) @OneToOne
Answer:
a) @ManyToOne
Explanation:
The @ManyToOne annotation indicates a many-to-one relationship between two entities.
19. In a Spring Data JPA repository, how can you indicate a method should delete by a specific field?
a) deleteByFieldName
b) removeByFieldName
c) eraseByFieldName
d) exterminateByFieldName
Answer:
a) deleteByFieldName
Explanation:
The convention in Spring Data JPA is deleteBy[FieldName] to indicate deletion by a specific field.
20. Which of the following denotes a derived delete query in Spring Data JPA?
a) deleteByFieldName
b) findByFieldName
c) queryByFieldName
d) readByFieldName
Answer:
a) deleteByFieldName
Explanation:
The naming convention deleteBy[FieldName] denotes a derived delete query in Spring Data JPA.
21. How can you perform pagination in Spring Data JPA?
a) Using the @Pageable annotation
b) Using the Page and Pageable interfaces
c) Using the @Pagination annotation
d) Using the Paginator class
Answer:
b) Using the Page and Pageable interfaces
Explanation:
In Spring Data JPA, pagination is achieved using the Page and Pageable interfaces.
22. In JPA, which strategy generates a primary key assigned by the database?
a) GenerationType.AUTO
b) GenerationType.SEQUENCE
c) GenerationType.IDENTITY
d) GenerationType.TABLE
Answer:
c) GenerationType.IDENTITY
Explanation:
The GenerationType.IDENTITY strategy indicates that the database should assign the primary key value.
23. Which annotation in JPA allows you to embed another object as part of your entity?
a) @Embeddable
b) @Embedded
c) @Include
d) @PartOf
Answer:
b) @Embedded
Explanation:
The @Embedded annotation is used to embed another object (annotated with @Embeddable) as part of your entity.
24. How can you control transaction management in Spring Data JPA?
a) By using the @Transactional annotation.
b) By configuring the transaction properties in the application.properties file.
c) By extending the JpaTransactionManager class.
d) By adding the @EnableTransactionManagement annotation to the configuration class
Answer:
a) By using the @Transactional annotation.
Explanation:
Transaction management in Spring Data JPA can be controlled by using the @Transactional annotation. By applying this annotation to service methods or repository methods, you can define transactional boundaries and control the behavior of database operations.
25. How can you define custom database queries in Spring Data JPA?
a) Using XML configuration files.
b) Using SQL scripts executed during application startup.
c) Using the @Query annotation and JPQL or native SQL queries.
d) Using external SQL files loaded at runtime.
Answer:
c) Using the @Query annotation and JPQL or native SQL queries.
Explanation:
Custom database queries can be defined in Spring Data JPA using the @Query annotation. By annotating a method with @Query and providing a JPQL (Java Persistence Query Language) or native SQL query, you can execute custom queries and retrieve the desired data.
26. Choose the correct Query Method:
Consider a Student entity:
@Entity@Table(name = "student")
public class Student {
@Id@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id")
private int id;
@Column(name = "first_name")
private String firstName;
@Transient// Field will not be saved in a database
private String lastName;
// getter and setter methods
}
Select the correct query method to find a student by firstName or LastName.
a) findByFirstNameOrLastName(String firstName, String lastName)
b) findByFirstNameAndLastName(String firstName, String lastName)
a) findByFirstNameOrLastName(String firstName, String lastName)
Explanation:
findByFirstNameOrLastName(String firstName, String lastName) - The method name follows the Spring Data JPA naming convention. It starts with the prefix "findBy," indicating that it will retrieve entities based on a specific condition. In this case, it searches for entities by first name or last name. The method parameters (String firstName, String lastName) represent the values that will be used to search for entities. It expects two String parameters: firstName and lastName, which represent the first name and last name to search for.
Conclusion
Congratulations on completing the Spring Data JPA Quiz! Spring Data JPA simplifies database access and provides convenient abstractions for working with relational databases in Spring applications. By testing your knowledge with these multiple-choice questions, you've gained a better understanding of Spring Data JPA concepts.
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