Capgemini interview question

Q. Can Static class inherited from derived/child Classes in c sharp?

A.    No

Let’s explorer it...

Step 1:- Create a static class and inherit the static class with derived/child class

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace StaticClass

{

    static class BaseClass

    {

        public static void Display()

        {

            Console.WriteLine("Base class Display()");

        }

    }

    class ChildClass : BaseClass

    {

        static void Main(string[] args)

        {

            BaseClass.Display();

        }

    }

}

When you inherit the static class with derived class, you will get the compile time error 'StaticClass.ChildClass': cannot derive from static class StaticClass.BaseClass'.

Note:-

1. When class is marked static, you cannot declare instance members in a static class.
2. Static members directly accessible with class name.

Q. What is the default modifier of class, method and properties in c sharp?

A.    Class default modifier is internal

      Method default modifier is private

      Properties default modifier is private   

Q. If class A contains class B and class B marked private and its member’s marked public, so can class A access the class B member’s?

A.    No, class B is inaccessible due to its protection level.

Let’s explorer it...

Step 1:- Create a class A and inside class A create class B and marked class B private.

    class A

    {

        private class B

        {

            public void Display()

            {

                Console.WriteLine("Class B Display()");

            }

        }

    }

    class C

    {

        static void Main(string[] args)

        {

            A objA = new A();

            A.B objB = new A.B();

            objB.Display();

        }

    }

You are not able to create the object of class B due to its protection level.

Q. What is SQL Commands?

A.    Data Definition Language (DDL)

CREATE, ALTER, DROP

Data Manipulation Language (DML)

SELECT, INSERT, UPDATE, and DELETE.

Data Control Language (DCL)

GRANT and REVOKE.

Transaction Control Language (TCL)

COMMIT, ROLLBACK, SAVEPOINT and SET TRANSACTION.

Q. Can we create a trigger on view? Or can we insert a record in view?

A.    Yes, we can create only instead of trigger on view.

Let’s explorer it...

Step 1:- Create Department and Employee table

CREATE TABLE Department

(

      DeptId int identity,

      DeptName varchar(10)

)

CREATE TABLE Employee

(

      EmpId int identity,

      DeptId int,

      EmpName varchar(10)

)

select * from Department

select * from Employee

Step 2:- Create View

create view View1

as

select a.DeptId,a.DeptName,b.EmpId,b.EmpName

from Department a

inner join Employee b on a.DeptId = b.DeptId

select * from View1

Step 3:- Insert record to View

insert into View1 values(1,'Account',2,'A')

You will get the following error:-

Msg 4405, Level 16, State 1, Line 30

View or function 'View1' is not updatable because the modification affects multiple base tables.

Step 4:- Create trigger on View

create trigger trg_Insert

on View1

instead of insert

as

begin

      insert into Department select DeptName from Inserted

      insert into Employee select DeptId,EmpName from Inserted

end

insert into View1 values(1,'Account',1,'Ram')

(1 row(s) affected)

(1 row(s) affected)

(1 row(s) affected)

select * from View1

DeptId	DeptName	EmpId	EmpName
1	Account	1	Ram

select * from Department

DeptId	DeptName
1	Account

select * from Employee

EmpId	DeptId	EmpName
1	1	Ram

drop table Department

drop table Employee

drop trigger trg_Insert

drop view View1

Q. ASP.NET Page Life Cycle

A.   

Stage	Description
Page request	The page request occurs before the page life cycle begins. When the page is requested by a user, ASP.NET determines whether the page needs to be parsed and compiled (therefore beginning the life of a page), or whether a cached version of the page can be sent in response without running the page.
Start	In the start stage, page properties such as Request and Response are set. At this stage, the page also determines whether the request is a postback or a new request and sets the IsPostBack property. The page also sets the UICulture property.
Initialization	During page initialization, controls on the page are available and each control's UniqueID property is set. A master page and themes are also applied to the page if applicable. If the current request is a postback, the postback data has not yet been loaded and control property values have not been restored to the values from view state.
Load	During load, if the current request is a postback, control properties are loaded with information recovered from view state and control state.
Postback event handling	If the request is a postback, control event handlers are called. After that, the Validate method   of all validator controls is called, which sets the IsValid property of individual validator controls and of the page. (There is an exception to this sequence: the handler for the event that caused validation is called after validation.)
Rendering	Before rendering, view state is saved for the page and all controls. During the rendering stage, the page calls the Render method for each control, providing a text writer that writes its output to the OutputStream object of the page's Response property.
Unload	The Unload event is raised after the page has been fully rendered, sent to the client, and is ready to be discarded. At this point, page properties such as Response and Request are unloaded and cleanup is performed.

Source 

Visit Microsoft.com

Q. How to get the total number of counts of Ram in both the table?

A.   

CREATE TABLE #Table1

(

      Name varchar(10)

)

CREATE TABLE #Table2

(

      Name varchar(10)

)

insert into #Table1 values('Ram')

insert into #Table1 values('Shyam')

insert into #Table1 values('Ghanshyam')

insert into #Table1 values('Gopal')

insert into #Table1 values('Ram')

insert into #Table2 values('Ram')

insert into #Table2 values('Shyam')

insert into #Table2 values('Ghanshyam')

insert into #Table2 values('Gopal')

insert into #Table2 values('Ram')

select * from #Table1

Name

Ram

Shyam

Ghanshyam

Gopal

Ram

select * from #Table2

Name

Ram

Shyam

Ghanshyam

Gopal

Ram

SELECT COUNT(*)

FROM

(

      SELECT NAME FROM #Table1

      UNION ALL

      SELECT Name FROM #Table2

) t

WHERE t.Name = 'Ram'

Results

4

drop table #Table1

drop table #Table2

Q. Where is GAC (Global Assembly Cache) located?

A.   

Starting with the .NET Framework 4, the default location for the global assembly cache is %windir%\Microsoft.NET\assembly.

In earlier versions of the .NET Framework, the default location is %windir%\assembly.

.Net Framework 4 and above

C:\Windows\Microsoft.NET\assembly or %windir%\Microsoft.NET\assembly

Below .Net Framework 4

C:\Windows\assembly or %windir%\assembly

Source

https://msdn.microsoft.com/en-us/library/yf1d93sz(v=vs.110).aspx

Q. How to install the assemblies in GAC?

A.   

Go to Start => All Programs => Visual Studio 2013 => Visual Studio Tools => Developer Command Prompt for VS2013

Note:-

You must have administrator privileges to use Gacutil.exe

Run following command

gacutil -i Complete Path of DLL

If you get the following error:

Failure adding assembly to the cache: Attempt to install an assembly without a strong name

Go to below URL and follow the given step

https://msdn.microsoft.com/en-us/library/ms247123(VS.80).aspx

If you completed the given step, go to Solution Explorer, from the Project menu. You will see .snk file is created.

Now, run the same command again. You will get the following successful message.

Assembly successfully added to the cache

To see added assemblies in GAC

Go to C:\Windows\Microsoft.NET\assembly\GAC_MSIL

Note:-

The folder name is created in GAC_MSIL folder with your Project namespace name.

For more info and how to uninstall the assemblies?  

Visit following link

https://msdn.microsoft.com/en-us/library/ex0ss12c(v=vs.110).aspx

Q. Function vs. Stored Procedure in SQL Server

A.   

The Function has only input parameter.

The Store procedure has input and output parameter.

The Function always returns a value.

The stored procedure is optional. It’s May or may not return a value.

The Function utilised only SELECT command.

The Store procedure utilised DDL (Data Definition Language), DML (Data Manipulation Language) command.

DDL- CREATE, ALTER, DROP

DML- SELECT, INSERT, UPDATE, DELETE

You cannot use try catch block in Function.

You can use try catch block in Store procedure.

You cannot use transactions in Function.

You can use transactions in Store procedure.

You cannot call Store procedure inside Function.

You can call Function inside Store procedure.

The Function can be used in Select statement.

The Store procedure can’t use in Select statement.

The Function called using SELECT.

The Store procedure called using EXEC or EXECUTE.