Master Hibernate and JPA with Spring Boot in 100 Steps - Step 48 - JPA Inheritance Hierarchies and Mappings - Mapped Sup

The video tutorial discusses the concept of mapped superclass in Java, explaining how it differs from entities and how it affects inheritance. It highlights the errors that can occur when using mapped superclass and provides solutions for retrieving part-time and full-time employees separately. The tutorial also compares mapped superclass with the table per class strategy, emphasizing the lack of inheritance hierarchy in mapped superclass. Finally, it concludes with a brief overview of the four options for mapping inheritance hierarchies and hints at future comparisons.

What is a mapped superclass primarily used for?

• To enforce inheritance hierarchy

• To act as an entity in the database

• To define common mappings for subclasses

• To create a table for each subclass

Why can't a mapped superclass be an entity?

• Because it is only for mapping purposes

• Because it is not annotated

• Because it lacks a primary key

• Because it is abstract

What error occurs when trying to retrieve employees using a mapped superclass?

• Employee not found

• Employee is not mapped

• Employee is abstract

• Employee is duplicated

How should part-time and full-time employees be retrieved when using a mapped superclass?

• By using inheritance

• By creating separate methods for each

• By joining tables manually

• Using a single query for all employees

What is the main difference between mapped superclass and table per class strategy?

• Table per class uses a single query

• Mapped superclass does not create tables

• Table per class does not support inheritance

• Mapped superclass creates a single table

In a mapped superclass strategy, how are common attributes handled?

• They are ignored

• They are stored in a separate table

• They are duplicated in each subclass

• They are defined in the superclass

What happens to the inheritance hierarchy when using a mapped superclass?

• It is partially maintained

• It is maintained as is

• It is completely eliminated

• It is converted to a single table