Top 20 Hibernate Interview Questions Answers 2020
Java developers around the world have struggled to find the best frameworks for their programming tasks. Different frameworks or frameworks...
We will begin our Hibernate tutorial with the most fundamental questions and answers. Once you become familiar with the topic, we will analyze more specialized topics that could be part of the questions in your job interview. Get ready and learn all about Hibernate!
Table of Contents
1.1 Question 1: Describe Hibernate.
1.2 Question 2: What is 'ORM'?
1.3 Question 3: Name some of the benefits of Hibernate
1.4 Question 4: What is the syntax for creating an SQL query?
1.5 Question 5: Define 'dialect'.
1.6 Question 6: Where are the mapping documents located within the framework?
1.7 Question 7: Name three main components of Hibernate.
1.8 Question 8: What is a 'Hibernate Session'?
1.9 Question 9: How can you configure Hibernate?
1.10 Question 10: What is the syntax for adding a parameter to the SQL query?
2 Questions in a Hibernate job interview: Advanced
2.1 Question 1: Name some of the advantages that Hibernate has over JDBC.
2.2 Question 2: What is 'SessionFactory'?
2.3 Question 3: What is the purpose of the 'cache' in Hibernate?
2.4 Question 4: Should you use your POJOs in Hibernate?
2.5 Question 5: Explain the 'persistent classes' in Hibernate.
2.6 Question 6: Should you use the standard Hibernate templates?
2.7 Question 7: Can you implement 'Join' in Hibernate using SQL?
2.8 Question 8: Name and define the three stages of objects in Hibernate.
2.9 Question 9: Name the standard cache in Hibernate.
2.10 Question 10: What is the main benefit of the Eclipse plugin?
In the first part of this Hibernate tutorial we will examine some of the questions in a simpler job interview. These sample questions are what you might be asked at the beginning of your interview, or if Hibernate is not the main framework in which your employers are interested. Even so, it is vital to know these questions and answers because they could be the turning point between a successful interview or fail completely.
Question 1: Describe Hibernate.
A great example of the first question they could ask you in your job interview, your potential employers could test your skills by describing the framework. You will surely encounter similar questions about Hibernate throughout the interview - those that require you to explain a concept or define something.
Hibernate is a Java based framework. It is designed to create applications based on databases. An important feature of the framework (and one of the main ones by which so many likes it) is that it represents the database in the form of objects . These objects can be written without having knowledge of SQL. It's great because it saves developers and programmers time - something of great value when it comes to Java programming! Hibernate also incorporates object mapping - which minimizes the number of lines of code needed for applications to work.
Question 2: What is 'ORM'?
ORM means ' Object-Relational Mapping ', it comes from the English “Object-Related Mapping”. It is a philosophy whose objective is to simplify the management and access to data. It succeeds (appointment on appointment) with the mapping of objects according to their data. It is a very basic concept on which Hibernate has been created, and is derived from Java (being an object-oriented programming language)
Question 3: Name some of the benefits of Hibernate
The Hibernate framework provides a wide variety of benefits for the developer and the Java programmer. However, the most important are: support for JPA and XML annotations, completely object-oriented, simple integration to other Java frameworks, automatic key generation.
Question 4: What is the syntax for creating an SQL query?
To create an SQL query in Hibernate, you would use this line of syntax:
Don't be surprised by similar questions during your Hibernate interview. The syntax is a very important aspect for the framework, so we have included examples of questions and answers of this type in this Hibernate tutorial that will surely ask you.
Question 5: Define 'dialect'.
A dialect could be a single file or a group of files (the latter is more common). These files are used to connect the Hibernate database with the Jav class a. You could say that the dialect is like the "translation tool" between Hibernate and its main database.
Question 6: Where are the mapping documents located within the framework?
All Hibernate mapping documents are located in what is known as the configuration interface . This interface is used both to store the mentioned documents and to issue specific configuration commands to the same framework.
This could be a complicated question in a job interview about Hibernate. Many employers might ask you something ¨ What is the configuration interface used in Hibernate? ¨. However, the question above has to do with the specific functions of the interface - you have to know the configuration interface well in order to answer correctly without problems. So stay tuned for similar questions!
Question 7: Name three main components of Hibernate.
There are more than three components to choose from, so you should have no problem answering this question. As an example, you could say: session , the mentioned configuration and query .
Question 8: What is a 'Hibernate Session'?
The Session is the main tool that performs the operation of the database within the Hibernate framework. It is the most important tool used to create, issue and execute queries based on SQL and HQL.
This is one of the questions in this Hibernate tutorial that you could deepen, starting with the fact that the thread of the Session in Hibernate is not safe, this means that each of the threads related to the Session can create and use their own ' instance of Session ', ensuring everything once the work is finished.
Question 9: How can you configure Hibernate?
The immediate answer would be that there are two main ways to do it - using XML and then the annotation provided by Java. However, this could be one of the complex questions about Hibernate. So what is the answer?
In versions prior to Hibernate 4.0, the only way to configure the framework was through XML. The option to do so with annotations based on Java programming were only available from version 4.0 onwards. That's why you should listen carefully to your potential employers with the questions in a Hibernate job interview - did they specify the framework version? What version are they talking about? Of course, the best answer is simply to respond with possible configuration methods and then go into detail - you will impress your interviewers!
Question 10: What is the syntax for adding a parameter to the SQL query?
The syntax would look like this:
Questions in a Hibernate job interview: Advanced
Now that we have finished the basic questions you might expect when you start your interview, let's move on to the second part of this Hibernate tutorial and review the advanced questions for the experienced Java programmer. These types of questions are what your potential employers could ask you to test your knowledge on the subject.
Although, don't worry - these advanced questions about Hibernate will only require a deeper answer or a more detailed explanation. If you are already familiar with Hibernate and are only looking in this Hibernate tutorial for questions to review before your interview (which is what I think), you will have no problem with the advanced questions.
Question 1: Name some of the advantages that Hibernate has over JDBC.
JDBC means Connectivity to Java databases . Hibernate has some advantages over JDBC, being some of the most popular: there is no need to download new drivers once you change the database, understanding SQL and HQL (JDBC can only use SQL), preinstalled drivers, etc.
Question 2: What is 'SessionFactory'?
Be careful not to confuse it with Session ! SessionFactory is what provides the Session instances. All non-standard data and information in Hibernate are saved in SessionFactory.
Question 3: What is the purpose of 'frisking' in Hibernate?
In Hibernate, caching allows you to run your application faster. Caching reduces the number of queries required to run the application successfully, and thus increase performance and speed.
Question 4: Should you use your POJOs in Hibernate?
This should be classified as a double question about Hibernate, because you need to know what a POJO is to answer correctly.
POJO is an acronym for Plain Old Java Object . These objects do not require a specific class, so they are not limited in any way or form. In fact it is recommended to use POJOs in your Hibernate projects - this because they provide a better and more effective code when compared to a standard Java class.
Question 5: Explain the 'persistent classes' in Hibernate.
One of the questions in a Hibernate interview that will require a deeper answer would be a good idea to investigate the topic in detail before your interview.
The persistent classes are Java classes that store your data (objects) within the tables of the database of the Hibernate framework. They are special in the sense that they need a construction set to function normally. The Proxies - some of the vital functions of Hibernate - greatly depend on the workflow persistent classes.
A good advice given by many experts in Java programming regarding job interviews is that you always deepen your answers, especially the advanced ones. By doing so, you not only show that you know the answer, but also that you know about the subject, in general. This is very true especially in questions like this - try to give a specific answer and then add about two or three sentences. By doing so, you will leave a good impression on your employers.
Question 6: Should you use the standard Hibernate templates?
Although this could be one of the questions in this more subjective Hibernate tutorial, your employers want to know if you know the general advantages of using Hibernate templates.
One of the main advantages of using Hibernate templates is that many functions are fully automated (closing Session , handling certain exceptions ) - you would have to issue and perform them manually otherwise. In addition, these templates greatly simplify the process of using Hibernate.
Question 7: Can you implement 'Join' in Hibernate using SQL?
Yes - in fact you can use both SQL and HQL queries to implement Join in Hibernate.
Question 8: Name and define the three stages of objects in Hibernate.
One of the questions in a more detailed Hibernate job interview, in total there are three object states - separate , persistent and transient .
The objects become separated once the session is closed by the Java programmer. Separated objects can become persistent with the appropriate methods activated. Persistent objects are the ones that open - they occur every time you save or retrieve certain instances of the Hibernate database. The transitory objects are the ¨ rare ¨ - they are the ones that have just been created and cannot be distinguished by a specific Session.
Question 9: Name the standard cache in Hibernate.
The standard Hibernate framework cache is EHCache .
Question 10: What is the main benefit of the Eclipse plugin?
The plugin helps the Java programmer write and manage their files easily compared to standard methods in Hibernate.
Now that we have examined in this Hibernate tutorial both the questions in a basic job interview and those focused on an experienced Java programmer, you surely have a clear idea of ??what you can expect in your Hibernate job interview. Remember - practice makes perfect! Don't stress too much and study this Hibernate tutorial at your own pace - this will increase the chance of getting your dream job!
If you know well how to use Hibernate and have studied in detail all the questions and answers in this Hibernate tutorial, you will increase your opportunities to get a well-paid job and achieve individual projects in the future. Although it is not a secret that many of those who learn Hibernate do it to get an excellent job, and how not to do it! Stable work, with above-average salary, good working conditions, future job opportunities - who doesn't want this?
Whatever your motivation to learn and study the questions in a job interview in this Hibernate tutorial, I hope you achieve your dreams! Be it the basic questions about Hibernate or the advanced questions in Java programming - I hope this Hibernate tutorial has been useful to you! Good luck!