Prev Next

Hibernate / Hibernate interview questions

Explain N+1 SELECT problem in Hibernate.

Hibernate ends up executing N+1 SQL queries to populate a collection of N elements referred as N+1 SELECT problem that occurs due to N+1 lazy loading and load on demand fetching strategy.

Let's say you have a collection of company objects (database rows), and each company has a collection of employee objects (database rows). In other words, company:employee is a 1-to-many relationship. If you need to iterate through all the companies, and for each one, print out a list of the employees, you have to perform one select to get all companies, and then N additional selects to find the list of employees, where N is the total number of companies.

More Related questions...

In a Parent-child relationship, how will you only access the columns from parent? Different between session.get() and session.load() in Java. @UniqueConstraint and @Column Unique attribute. Difference between save and persist. Difference between Hibernate createCriteria, createQuery, createSQLQuery. What is HQL (Hibernate Query Language)? Difference between @NotNull, @NotEmpty and @NotBlank. What are the most common methods of Hibernate configuration? What is ORM ? What is hibernate? What does ORM consists of ? @Repository @Embeddable @Service @Controller Differentiate JPA and hibernate. What are the ORM levels ? Why do you need ORM tools like hibernate? core interfaces of Hibernate. Is SessionFactory a thread-safe object? What role does the SessionFactory interface play in Hibernate? Is Hibernate Session a thread-safe object? What are the different states of object in hibernate? How to make a immutable class in hibernate? Different types of association in hibernate. Is it possible to perform collection mapping with One-to-One and Many-to-One? What is lazy loading in hibernate? What is the difference between merge and update ? How do you define sequence generated primary key in hibernate? What are the Collection types in Hibernate ? What is Hibernate proxy? What are Callback interfaces? What are the types of inheritance models in Hibernate? Benefits of hibernate over JDBC? Session Interface. SessionFactory Interface. Configuration Interface. Transaction Interface. Query and Criteria Interface. What are Callback interfaces? What is POJO? Detached Criteria Advantages of Detached criteria. Explain N+1 SELECT problem in Hibernate. List the strategies to eliminate the N+1 SELECT problem in Hibernate. Explain high level architecture of Hibernate framework. How do we see hibernate generated SQL on console? Hibernate: Can a Entity Class be declared final? How to call stored procedure in Hibernate? Explain transaction management in hibernate. Difference between fetch mode and fetch type in Hibernate. What is the default fetch mode in Hibernate? What is the difference between FetchType.LAZY and FetchType.EAGER in Java Persistence API? Difference between using a @OneToMany and @ElementCollection annotation in Hibernate. Explain the features introduced in Hibernate 5. Which throws Exception when no row found: session.load vs session.get. Difference between criteria and HQL In hibernate.
Show more question and Answers...

Hibernate interview questions II

Comments & Discussions

Interviews Questions

About Javapedia.net

Javapedia.net is for Java and J2EE developers, technologist and college students who prepare of interview. Also this site includes many practical examples.

This site is developed using J2EE technologies by Steve Antony, a senior Developer/lead at one of the logistics based company.

Follow Javapedia updates

contact: javatutorials2016[at]gmail[dot]com

Kindly consider donating for maintaining this website. Thanks.

Copyright © 2026, javapedia.net, all rights reserved. · .

DMCA.com Protection Status