Hibernate Framework Hibernate Associations and Relationships 3

Question 1

What happens when CascadeType.ALL is specified on a Hibernate association?

Accepted Answer

All JPA lifecycle operations cascade to the associated entity

Answer

Only PERSIST and MERGE operations cascade to the child

Answer

Only DELETE operations cascade to the child

Answer

The relationship automatically becomes bidirectional

Question 2

In a bidirectional @ManyToMany relationship, which side should contain the @JoinTable annotation?

Accepted Answer

The owning side — the side without 'mappedBy'

Answer

Both sides must declare @JoinTable

Answer

Neither side; Hibernate generates the table automatically

Answer

The inverse side — the side with 'mappedBy'

Question 3

What defines a 'unidirectional' association in Hibernate?

Accepted Answer

An association where only one entity holds a reference to the other

Answer

An association where only one entity can save changes

Answer

An association that can only be traversed in one direction in SQL

Answer

An association where cascading applies on only one side

Question 4

In a @JoinTable annotation, which attribute defines the foreign key columns referencing the inverse (non-owning) entity?

Accepted Answer

inverseJoinColumns

Answer

joinColumns

Answer

referencedColumns

Answer

foreignKeyColumns

Question 5

What does fetch = FetchType.EAGER mean for a Hibernate association?

Accepted Answer

The associated entity is loaded immediately along with the parent entity

Answer

The associated entity is loaded only when its getter is called

Answer

The associated entity is loaded in a background thread

Answer

The associated entity uses batch size fetching

Question 6

What is the 'N+1 select problem' in the context of Hibernate associations?

Accepted Answer

1 initial query to load N parent entities followed by N additional queries to load each entity's associations

Answer

N queries needed to insert 1 record with associations

Answer

N entities referencing 1 shared foreign key causing conflicts

Answer

N+1 join conditions making queries too complex

Question 7

Which Hibernate strategy resolves the N+1 select problem by fetching associations in a single query using SQL JOINs?

Accepted Answer

JOIN FETCH in HQL or Criteria API

Answer

FetchType.LAZY with batch size

Answer

CascadeType.REFRESH on the association

Answer

Second-level cache on the child entity