Code360 powered by Coding Ninjas X Naukri.com. Code360 powered by Coding Ninjas X Naukri.com
Table of contents
1.
Introduction
2.
Most Asked Entity Framework Interview questions
2.1.
1. What is meant by Entity Framework?
2.2.
2. What are the features of Entity Framework?
2.3.
3. What is the difference between ADO.NET and Entity Framework?
2.4.
4. What is Code First approach in Entity Framework?
2.5.
5. What is a Conceptual Model? 
2.6.
6. What is the primary benefit of using Entity Framework or EF?
2.7.
7. What are the disadvantages of Entity Framework?
2.8.
8. How can you use Entity Framework in MVC to retrieve data from a database?
2.9.
9. What is a Storage Model?
2.10.
10. What are Micro ORMs?
2.11.
11. What additional O/RMs are there that you can utilize with.NET applications?
2.12.
12. Define Dapper.
2.13.
13. In Entity Framework, what is migration?
2.14.
14. What is a DBContext class and what does it do?
2.15.
15. What are the benefits of the Model First Approach?
2.16.
16. What exactly is in an .edmx file?
2.17.
17. Explain the significance of the T4 entity in the Entity Framework.
2.18.
18. How can you load related entities in EF (Entity Framework)?
2.19.
19. What are the advantages and disadvantages of the Database First Approach?
2.20.
20. How does Entity Framework handle concurrency?
2.21.
21. What are Entity Framework POCO classes?
2.22.
22. What are the Entity Framework Architecture components?
2.23.
23. What is an Entity Data Model?
2.24.
24. Explain the different parts of the Entity Data Model?
2.25.
25. What is LINQ to entities?
2.26.
26. What is the EF Data Access Architecture?
2.27.
27. What is the DataAdapter class in ADO.NET?
2.28.
28. What is the difference between connected and disconnected data access in ADO.NET?
2.29.
29. What exactly is Optimistic Locking?
2.30.
30. What are the key functionalities offered by the Entity Framework?
2.31.
31. Discover the various types of inheritance that Entity Framework supports.
2.32.
32. Explain the concept of database concurrency and discover effective strategies for managing it.
2.33.
33. Explain the ways to increase performance of Entity Framework?
2.34.
34. What is meant by the Entity SQL?
2.35.
35. What is meant by the SQL injection attack?
3.
Frequently Asked Questions
3.1.
Which approach is best for Entity Framework?
3.2.
What are the 3 approaches in Entity Framework?
3.3.
In which scenarios can we use Entity Framework?
3.4.
What are some arguments against Entity Framework?
4.
Conclusion
Last Updated: Jun 12, 2024
Medium

Top Entity Framework Interview Questions in 2023

Master Power BI using Netflix Data
Speaker
Ashwin Goyal
Product @
18 Jun, 2024 @ 01:30 PM

Introduction

Entity Framework is a Microsoft-supported open-source ORM framework for .Net applications. It allows developers to work with data using domain-specific objects rather than the underlying database tables and columns where the data is stored. When working with data, developers can work at a higher level of abstraction with the Entity Framework, allowing them to create and maintain data-oriented applications with less code than traditional applications.

The popularity of tools like the Entity framework can be attributed to the rise of .NET. If you wish to advance your career in the field of .NET and other related technology, you will be encountering Entity framework, as you’ll be needing to answer Entity framework interview questions you must go through this article. This article will discuss the most essential Entity framework interview questions, so let’s get started.

Top Entity Framework Interview Questions and Answers (2023

Also see, Html interview questions

Most Asked Entity Framework Interview questions

1. What is meant by Entity Framework?

Ans: ADO.NET Entity Framework is an ORM (object-relational mapping) that extends ADO.NET components to produce a higher abstract object model. Instead of working with datasets, datatables, commands, and connections as illustrated in the code below, you interact with higher-level domain objects such as customers, suppliers, and so on.

2. What are the features of Entity Framework?

Ans: Entity Framework is an ORM framework for.NET offer features like data modeling using classes, LINQ integration for querying, support for different database providers, automatic code generation, change tracking for simple persistence, and choices for lazy or eager loading of related data.
 

3. What is the difference between ADO.NET and Entity Framework?

Ans: The following are the differences between ADO.NET and Entity Framework:

difference between ADO.NET and Entity Framework

4. What is Code First approach in Entity Framework?

Ans: We avoid using Entity Framework's Visual Designer when using the Code First technique. To put it another way, the EDMX file is not included in the solution. As a result, you now have complete control over both the context and entity classes.

5. What is a Conceptual Model? 

Ans: The model classes that include the relationships are known as conceptual models. These aren't affected by the database's design.

6. What is the primary benefit of using Entity Framework or EF?

Ans: The main advantage of using Entity Framework (EF) is that it automatically generates code for the Model (Middle Layer), Mapping code, and Data Access Layer. It saves a significant amount of time during the development process.

7. What are the disadvantages of Entity Framework?

Ans: There are certain disadvantages to Entity Framework, including as performance overhead because of its abstraction layer, the potential for created SQL inefficiencies, a lack of control over complex queries, and a learning curve for advanced functionality. If not used carefully, it could also result in ineffective database architectures.

8. How can you use Entity Framework in MVC to retrieve data from a database?

Ans: The following are the steps to retrieve data from a database in Model View Controller using Entity Framework:

  • Create a new project
  • Add the Entity Framework reference to the NuGet package manager
  • Within the table structure, create a new class in the model
  • Add the connection string to the name of the web.config.connection string so that it matches the context
  • Open Global.asax.cs, add the Entity Framework extra namespace and then initialize the database
  • Right-click the Controller folder, then go to the Namespace section and add a new controller and model reference
  • Add the sections you want to see by right-clicking on the controller's name

9. What is a Storage Model?

Ans: Our database design models are called Storage Models, and they include database tables, views, stored procedures, and keys with relationships.

10. What are Micro ORMs?

Ans: Instead of generating, altering, or tracking changes, a Micro ORM is designed to focus on the most crucial task of working with database tables. Both EF 6.x and EF Core are O/RMs since they offer comprehensive functionalities.

11. What additional O/RMs are there that you can utilize with.NET applications?

Ans: You can utilize the following O/RMs with.NET applications:

  • Dapper
  • Entity Framework Core 6.x
  • Entity Framework 6.x
  • N Hibernate

12. Define Dapper.

Ans: For the.NET world, Dapper is a simple/micro ORM. The StackOverflow team designed Dapper to address their difficulties and made it open source. It's a NuGet library for database operations that can be included in any .NET project.

13. In Entity Framework, what is migration?

Ans: When your model changes, Entity Framework introduced a migration tool that adjusts the database schema without losing any existing data or database objects.

There are two kinds of Migration:

  • Code-based Migration
  • Automated Migration

14. What is a DBContext class and what does it do?

Ans: DBContext represents the database connection and a set of tables, while DBSet represents the tables themselves. The DBContext lets you use a connection string to connect your model properties to your database (probably using Entity Framework).

Later on, you'll use the DBContext to refer to a database in your controller to handle data.

15. What are the benefits of the Model First Approach?

Ans: Model first approach provides the flexibility to design Entity Models independently and allows for later stage improvement.

Model classes can be created by drawing them in the edmx designer, so there is no need for a large database.

16. What exactly is in an .edmx file?

Ans: An XML file with the extension .edmx declares a conceptual model, a storage model, and the mapping between these models. This file also contains the data that ADO.NET entity data model designer uses to render a model graphically. It contains all of the mapping details for how an object maps to SQL tables. It is classified into three types: SSDL, CSDL, and MSL.

Check this out: jQuery interview questions

17. Explain the significance of the T4 entity in the Entity Framework.

Ans: T4 entities are critical in Entity Framework because they are at the heart of entity framework code generation. It reads the EDMX XML file and generates C# code behind the scenes.

18. How can you load related entities in EF (Entity Framework)?

Ans: There are three ways to load related entities or data into EF.

  • Loading with zeal
  • Explicit Loading
  • Lazy Loading

19. What are the advantages and disadvantages of the Database First Approach?

Ans: The advantages and disadvantages of Database First Approach are following:

1. Advantages:

If an existing database exists, it is simple to create entity models.

For data-intensive applications, this is the preferred method.

2. Disadvantages:

A massive amount of code is generated when we create a .edmx file from an existing database.

We must extend the models if we want to add additional functionality to the models generated.

20. How does Entity Framework handle concurrency?

Ans: Concurrency is handled in EF by using optimistic locking. To use optimistic locking, right-click on the EDMX designer and select Fixed as the concurrency mode. You should now receive an OptimisticConcurrencyException error whenever we have a concurrency problem.

21. What are Entity Framework POCO classes?

Ans: POCO is an abbreviation for Plain Old C# Object. EDMX generated classes that are cluttered with entity tags. We frequently want to use simple.NET classes and integrate them with the Entity Framework.

22. What are the Entity Framework Architecture components?

Ans: The following are the Entity Framework components:

  • Entity SQL 
  • Object Service 
  • Entity Data Model (EDM) 
  • LINQ to Entities
  • ADO.Net 
  • Data Provider 
  • Entity Client Data Provider

23. What is an Entity Data Model?

Ans: An entity data model (EDM), which is independent of the underlying database schema, is a conceptual representation of the data in a database. EDM is represented in Entity Framework by a collection of classes that provide the organization of entities (objects) and connections between them.

It acts as a connection point between the application and the database, enabling programmers to handle data in an object-oriented way. Entities, affiliations, and mappings between entities and the database tables are all included in this model.

24. Explain the different parts of the Entity Data Model?

Ans: There are three primary components to the entity data model (EDM):

  • Conceptual Model: It illustrates how the application views the data conceptually. It describes entities (things), their attributes, and their connections with one another. In an object-oriented programming language like C# or VB.NET, it is often specified via classes
     
  • Storage Model: It shows how the underlying database is organized. It consists of tables, views, keys, and other components unique to databases. By using the database schema, it is represented
     
  • Mapping: These show how the conceptual model and the storage model relate to one another. It details the mapping of entities' properties to database columns and tables. This step makes sure that data is correctly stored in the database and retrieved when needed
     

25. What is LINQ to entities?

Ans: LINQ to Entities is query language which we use to write queries against the object models and the resultant query will return the entities defined in the Conceptual Model.

26. What is the EF Data Access Architecture?

Ans: The ADO.NET Framework supports two Data Access Architecture models:

  • Interested in making connections
  • Disconnected


EF employs the Disconnected model (no connections are left open). Because you work with data and make desired changes before performing the SaveChanges. A context in an N-tier application either creates or saves entities, but not both. It generates entities that are serialized and dispose of the context. Entities that return from the client application are deserialized and reattached to a new context instance, where their changes are saved.

27. What is the DataAdapter class in ADO.NET?

Ans: The ADO.NET data-adapter class retrieves data from a database, stores it in a dataset, and then return changes to the database. Data-adapter serves as an intermediary for all types of communication. Data-adapter fills data into a Data-table using the Fill() method.

28. What is the difference between connected and disconnected data access in ADO.NET?

Ans: Connected data access: You can have connected data access by using the DataReader objects of the data provider. It allows for quick access to data but does not allow for editing.

Disconnected data access: Disconnected data access is accomplished using the DataAdapter object. The dataset is editable and works independently of the database.

29. What exactly is Optimistic Locking?

Ans: Optimistic locking is a strategy that involves reading a record, noting a version number (other methods include dates, timestamps, or checksums/hashes), and ensuring that the version hasn't changed before writing the record back. When you write the record back, you filter the version update to ensure it's atomic. (that is, it hasn't been updated between the time you check the version and write the record to the disc) and update the version in a single hit.

If the record is dirty (i.e., a different version than yours), the transaction is aborted and the user can restart it. This strategy is best suited for high-volume systems and three-tier architectures where a connection is not always maintained.

30. What are the key functionalities offered by the Entity Framework?

Ans: The key functionalities offered by the Entity framework are Object-relational mapping, LINQ integration, change tracking, CRUD operations, Lazy loading, transactions, and database-first approaches.

31. Discover the various types of inheritance that Entity Framework supports.

Ans: There are three types of inheritance:

  • Table Par Hierarchy(TPH): In this, all classes in an inheritance hierarchy are mapped to a single table. It puts all the fields for each type into a single table. After that, it uses the discriminator field to differentiate the types
     
  • Table Per Type(TPT): It is similar to the TPH, but in this, each class in the inheritance has its own table
     
  • Table Per Concrete Class: It creates a separate table for each concrete class and stores its fields in that separate table

32. Explain the concept of database concurrency and discover effective strategies for managing it.

Ans: Database concurrency is the ability to handle multiple concurrent transactions and it modify the data simultaneously. Below are some strategies:

  • Optimistic concurrency: It assumes that conflicts are rare and each transaction reads the data without locking it. If no conflicts occur, then the changes are committed. Otherwise, it aborts the transaction
     
  • Pessimistic concurrency: It assumes that conflicts are likely between concurrent transactions. This method ensures access to the data but can lead to the degradation of performance
     
  • Row versioning: This strategy includes that each row in the database has a version number, and it gets updated when a transaction modifies a row

33. Explain the ways to increase performance of Entity Framework?

Ans: Make use of eager loading, compiled queries, and stay away from the N+1 query problem to improve Entity Framework speed. When performing bulk updates, disable auto-detect changes and use AsNoTracking() for read-only data. Use batch updates for efficiency and stored processes for complex operations; avoid loading unneeded data. Design and index your database properly to maximize it. Reduce the number of lengthy transactions, and think about utilizing AsQueryable() with LINQ-to-Objects.

34. What is meant by the Entity SQL?

Ans: Entity SQL is a query language that allows developers to query conceptual models in the entity framework. Conceptual models represent the data as relationships, and Entity SQL allows users to query those relationships.

35. What is meant by the SQL injection attack?

Ans: SQL injection is a type of security attack. It inserts malicious SQL code into user inputs or backend databases, which can manipulate the application’s SQL statements and potentially gain unauthorized access. This can lead to data breaches and unauthorized data exposure.

Get the tech career you deserve, faster!
Connect with our expert counsellors to understand how to hack your way to success
User rating 4.7/5
1:1 doubt support
95% placement record
Akash Pal
Senior Software Engineer
326% Hike After Job Bootcamp
Himanshu Gusain
Programmer Analyst
32 LPA After Job Bootcamp
After Job
Bootcamp

Frequently Asked Questions

Which approach is best for Entity Framework?

The best approach for Entity Framework depends on the project requirements. Some prefer Database-First for working with legacy databases, while others prefer Code-First for more control over the database schema. Model-First can be a good option for visualizing and designing the data model.

What are the 3 approaches in Entity Framework?

There are three approaches to Entity Framework: 

  • Database-First starts with an existing database.
  • Model-First starts with the conceptual model of the data.
  • Code-First starts with the code and develops the database schema.

In which scenarios can we use Entity Framework?

Entity Framework can be used in scenarios where .NET applications need to interact with a database. It is used for creating, reading, updating, and deleting data, mapping between data tables and object-oriented entities, and managing database-related operations.

What are some arguments against Entity Framework?

Arguments against Entity Framework contain problems over performance and generated SQL code, difficulty working with complex database structures, and limitations in certain scenarios, such as working with NoSQL databases.

Conclusion

In this article, we have extensively discussed basic Entity framework Interview questions, intermediate Entity framework Interview questions, along with advanced Entity framework Interview questions.

We hope that this blog has helped you enhance your knowledge about the Entity framework Interview questions and if you would like to learn more, check out our articles ASP.NET and .NET Framework.

You can also check Interview Experiences and Interview Preparation Resources if you are interested in cracking the technical interviews at top Product-based companies like Amazon, Microsoft, Uber, etc. You can also consider our Interview Preparation Course to give your career an edge over others.

Do upvote our blogs if you find them helpful and engaging!

Happy Learning!

Previous article
ElasticSearch Interview Questions
Next article
ES6 Interview Questions
Live masterclass