SQL

 DDL -> Data Definition Language

Create, Drop , Alter, Truncate, Comments

DQL -> Data Query Language

Select, From, Where, Group by

DML-> Data Manipulation Language

Insert , Update, Delete

DCL -> Data Control Language

Grant, Revoke

TCL-> Transaction Control Language

Begin Tran, Commit , Rollback , Save point

Microservices Questions and Answer

 How the .NET core kestrel web server Works?

 Libuv manager I/O

Sagar Pattern

Breaks a transaction into a sequence of smaller local  transaction . If a step fails , They system executes compensating transactions to undo preceding changes

CQRS

Command Query Responsibility segregation

Command - one Microservices

Query - One Microservices 

Idempotency

• When same button pressed multiple time
• API header Need to add with Idempotency-key 
• IMemoryCache - will hold the key and handle id(Redis cache)

ConCurrency

     If a same resources in the requested multiple time

     Lock - Feature

Rate Limiter

• No. of request a client can make to your API in a time frame
• Middleware need to configure

React js Question and answers

 

What are React JS data transfer techniques	1.Prop drilling        a. Parent to child        b. Child to Parent(usecallback) 2. Global state sharing – Context API 3. state management lib redux 4. React Route URL (useParams)
Reactjs components lifecycle	1.Mounting       a. constructor       b.getderivedstatefromprop       c.render       d.componentsdidmount 2.Updating      a.getderivedstatefromprop      b.shouldcomponentupdate       c.render       d.getsnapshotbeforeupdate       e.componentsdidupdate   3.Unmounting      a.componentWillUnmount
How to post data using React js	Fetch Axios
How to post data using Node js	Express js Axios
i have to post 100 different request and get response at same time in react js	Promise All   Promise.allSettled

10+ Years Question and answers

 1.Globalization(Application that function for multiple cultures- Using unicode, Formatting date, number and currencies calender) vs localization(cluture translation text , adapting UI elements and Adjusting image and icons)

Resources.resx(using system.Resources)

2.Event Driven architecture (Event Source, Event, Event Broker/Event Bus , Publisher, Subscriber, Event Handler , Dispatch)

3.Eventhandler(event keyword) vs function pointers(delegate)

4.IOC - DIO

5. Reflection 

6. System.IO - read and write files using streamwriter and streamreader

7. Hashmaps in c# - dictionary<string,int>

Add,containskeys,remove

8. Use an eager loading ienumerable( not benefit from deferred execution)

Use a Lazy loading Iqueryable ( defers execution of the entire query until output is required)

9. Null Coalescing Operator - a=b??c; means if b is null then a will be assigned the value of c

10. Example for boxing and unboxing 

Is - reference, boxing and unboxing 

As- nullable, Reference and boxing

11. In Web API header

Content-Type: request body

Accept : response format

12. In web API 

Httpget - will not have the body , it will need only the query params

Httpost - will have the body params

10+ Years .NET Interview Questions and answers

1. Sql profiler - performance tracking

2. Sql where group by having order by

3.Mediator design pattern - reduce direct connection between classes and promote loose coupling and easier code maintenance 

4.singletone object creating - private constructor creating the object inside the static method getinstance with in the same class

5. Finally (After try block it will run every time) vs disposes(using keyword will dispose it automatically when square bracket ends. Explicit implementation: IDispose)

6.Dictionary (Generic type , typecasing is not required) vs hash table(Non Generic type , typecasting is required)

7.Corse- domain check

8.Crossed side scripting - encoding - httputility.HtmlEncode(userInput)

9.Convariance(more derived type to a less derived type(get)(generic interface - out keyword) and conravarient(less derived type to more derived type(set)(in keyword))

10. JWT Token will access the keyvault: 

When a client request access to key vault , it must authenticate with Microsoft Entra ID to obtain an OAuth token(Using Cryptography Client to sign the token with the key)

11. Thread lock in C# - Using Lock

 Keyword

12. Task ( asyn operation using Task parallel library , )VS Thread( Parallel execution of code)

13. Background process in .netcore?

IHostedservice interface and backgroundservice class

14. Code optimization in API 

15. Statefull (RESTFULL)(more complex interaction)(Shopping carts - HttpContext.Session.GetObjectFromJson<List>)

 vs

 Stateless(REST) ( do not store client data between request)(public Api weather service)(Each request from a client to service must contain all the information for process the request)

16. AddSession. Idletimeout property in configuration service in startup.cs

17.Soap VS Rest

18.Use of nugget packages

19. Request Delegates in .Net Core

20.Di containers

21. Irepository design pattern 

22. Can abstract class can have constructor - yes

23.Acid principle

24. Mapper in ops

25. Repository design patten

26.Html 5 relation

27.Access token vs refresh token

28.Exceptional handling- trypass

29.Rapidmq

30.Kafka- ques system 

31. Onion Artich

32.Value type - bool

33. Ref type 

34. SQL Pivot 

35. Thread vs task vs syn vs asyn

36. Catching

37.Dependency injection in core

38. Breakpoint in azure

39. .net core Dependency injection (t,scope,singleton)

40. .net core iconfiguration getsection .value get value ioption 

@ CORS- 

41.unauthorized requests to a different domain(keyword : enablecors, disablecors)

42.React

Useeffect -syntext

Arrr[1,2,2,3]

Humanaan

------------

• Singleton design 
• Dispose and finally 
• Boxing and unboxing
• Unmanaged vs managed code
• Early and lazy binding 
• Entity framework 
• Dependency injection in .net core
• Inbuilt container for DI
• .net core VS .net classic 
• Nuget package usage
• Startup.cs what is used
• Use of program.cs
• Service registration in startup.cs
• www.root folder
• App.setting.json
• Session and state management in .net core
• Rest in webapi
• SOAP vs Rest
• Token based authentication
• SQL - SQL Profile 

Complex thing I have faced 

 Stub and external service in logic for the startup.cs

List Remove VS RemoveAt

 List Remove - will remove the value from the list

List RemoveAt - will remove the index value 

List Remove 

List<int> intsList = new List<int>();

intsList.Add(100);

intsList.Add(200);

intsList.Add(300);

intsList.Add(400);

intsList.Add(500);

intsList.Remove(1);

Console.WriteLine("TOTAL COUNT "+intsList.Count);

foreach (int i in intsList)

{

    Console.WriteLine(i);

}

OUTPUT:

List RemoveAt

List<int> intsList = new List<int>();

intsList.Add(100);

intsList.Add(200);

intsList.Add(300);

intsList.Add(400);

intsList.Add(500);

intsList.RemoveAt(1);

Console.WriteLine("TOTAL COUNT "+intsList.Count);

foreach (int i in intsList)

{

    Console.WriteLine(i);

}

OUTPUT : 

ArrayList Remove VS RemoveAt Example

 ArrayList with RemoveAt

ArrayList arrayList = new ArrayList();

arrayList.Add("1");

arrayList.Add("2");

arrayList.Add("3");

arrayList.Add("4");

arrayList.Add("5");

arrayList.RemoveAt(2);

Console.WriteLine(arrayList.Count);

OUTPUT:

ArrayList with Remove

ArrayList arrayList = new ArrayList();

arrayList.Add("1");

arrayList.Add("2");

arrayList.Add("3");

arrayList.Add("4");

arrayList.Add("5");

arrayList.Remove("2");

Console.WriteLine("TOtal count: "+arrayList.Count);

foreach (string i in arrayList)

{

    Console.WriteLine(i);

}

OUTPUT: