Find nth highest and lowest salary of an Employee

This question has been asked many times in interview to candidate that find or fetch nth highest and lowest salary of an Employee like 2nd, 3rd, 4th, 5th… highest and lowest salary of an Employee from Employee table. This question some times also asked as get nth highest and lowest salary of an Employee without using TOP and sub query. Let’s see solutions for all this questions in this article.

Suppose we have following table of Employee with Name and Salary of Employee.

Query to get nth(3rd) highest salary of an Employee

Suppose we want to get 3rd highest salary of an Employee so query should be like.

select top 1 Salary as '3rd highest salary' from (select distinct top 3 Salary from Employee order by Salary desc)   a order by Salary asc

Let me illustrate above query as here we want to fetch nth(3rd) highest salary of an Employee so first inside sub query we find all top n(3) distinct records using order by descending which result in to top n(3) records with highest salary and than we fetch top 1 record among all these records with order by ascending which full fill our requirement to find nth(3rd) highest salary of an Employee.

Query to get nth(3rd) lowest salary of an Employee

select top 1 Salary as '3rd lowest salary' from (select distinct top 3 Salary from Employee order by Salary asc)   a order by Salary desc

See here we want to find nth(3rd) lowest salary of an Employee so our logical of fetching data will be reversed so first inside sub query we find all top n(3) distinct records using order by ascending which result in to top n(3) records with lowest salary and than we fetch top 1 record among all these records with order by descending which full fill our requirement to find nth(3rd) lowest salary of an Employee.

Query to get nth(3rd) highest salary of an Employee without using TOP and Sub Query

This question also can twisted to find or fetch nth(3rd) highest salary of an Employee without using TOP and Sub Query so solutions can be using With CTE(Common Table Expressions) as below query.

WITH Salaries AS( SELECT distinct Salary, ROW_NUMBER() OVER(ORDER BY Salary DESC) AS 'RowNum'     FROM Employee)SELECT Salary FROM Salaries WHERE RowNum = 3

in above query we find salary in descending order using With CTE(Common Table Expression) than we used RowNum = n(3) which results into nth(3rd) highest salary of an Employee without using TOP and Sub Query.

Query to get nth(3rd) lowest salary of an Employee without using TOP and Sub Query

To find or fetch nth(3rd) lowest salary of an Employee without using TOP and Sub Query so solutions can be using With CTE(Common Table Expressions) as below query.

WITH Salaries AS(SELECT distinct Salary, ROW_NUMBER() OVER(ORDER BY Salary asc) AS 'RowNum'     FROM Employee)SELECT Salary FROM Salaries WHERE RowNum = 3

in above query we find salary in ascending order using With CTE(Common Table Expression) than we used RowNum = n(3) which results into nth(3rd) lowest salary of an Employee without using TOP and Sub Query.

What is cookie? ADVANTAGES AND DISADVANTAGES OF COOKIES

What is cookie?
A cookie is a small piece of text file stored on user's computer in the form of name-value pair. Cookies are used by websites to keep track of visitors e.g. to keep user information like username etc. If any web application using cookies, Server send cookies and client browser will store it. The browser then returns the cookie to the server at the next time the page is requested. The most common example of using a cookie is to store User information, User preferences, Password Remember Option etc.It is also one of the common and mostly asked interview questions.

Some facts about Cookie

Here are a few facts to know about cookies:

Cookies are domain specific i.e. a domain cannot read or write to a cookie created by another domain. This is done by the browser for security purpose.
   
Cookies are browser specific. Each browser stores the cookies in a different location. The cookies are browser specific and so a cookie created in one browser(e.g in Google Chrome) will not be accessed by another browser(Internet Explorer/Firefox).
 
Most of the browsers store cookies in text files in clear text. So it’s not secure at all and no sensitive information should be stored in cookies.
 
Most of the browsers have restrictions on the length of the text stored in cookies. It is 4096(4kb) in general but could vary from browser to browser.

Some browsers limit the number of cookies stored by each domain(20 cookies). If the limit is exceeded, the new cookies will replace the old cookies.

Cookies can be disabled by the user using the browser properties. So unless you have control over the cookie settings of the users (for e.g. intranet application), cookies should not be used.

Cookie names are case-sensitive. E.g. UserName is different than username.
Advantages of using cookies
Here are some of the advantages of using cookies to store session state.

Cookies are simple to use and implement.

Occupies less memory, do not require any server resources and are stored on the user's computer so no extra burden on server.

We can configure cookies to expire when the browser session ends (session cookies) or they can exist for a specified length of time on the client’s computer (persistent cookies).

Cookies persist a much longer period of time than Session state.

Disadvantages of using cookies

Here are some of the disadvantages:

As mentioned previously, cookies are not secure as they are stored in clear text they may pose a possible security risk as anyone can open and tamper with cookies. You can manually encrypt and decrypt cookies, but it requires extra coding and can affect application performance because of the time that is required for encryption and decryption

Several limitations exist on the size of the cookie text(4kb in general), number of cookies(20 per site in general), etc.

User has the option of disabling cookies on his computer from browser’s setting .

Cookies will not work if the security level is set to high in the browser.
 
Users can delete a cookies.

Users browser can refuse cookies,so your code has to anticipate that possibility.
 
Complex type of data not allowed (e.g. dataset etc). It allows only plain text (i.e. cookie allows only string content)

How to find whether a string contains any of the special characters?

 Regex RgxUrl = new Regex("[^a-z0-9]");
                    blnContainsSpecialCharacters = RgxUrl.IsMatch(stringToCheck);

========================================================

public static bool IsSpecialCharacters(this string stringToTest)
       {
           //const string charSet = "[^a-z0-9]";
             const string charSet = "[^a-zA-Z0-9]";

           //Regex RgxUrl = new Regex("[^a-z0-9]");
           //blnContainsSpecialCharacters = RgxUrl.IsMatch(stringToCheck);

           return Regex.Match(stringToTest, @"^[" + charSet + @"]+$").Success;
       }

MVC4 site publish to Somee

Run As Admin mode in Visual stu..

Publish method: FTP

Server: ftp://[YOUR USERNAME].somee.com

Site path: /www.[YOUR USERNAME].somee.com/ 

Passive mode: Checked 

User name: [YOUR USERNAME] 

Password: [YOUR PASSWORD] 

how to paste in cmd prompt using keyboard.. without mouse

 ALT+ Space  E  P : ALT+Space for System Menu E for Edit sub-menu P for Paste item ... njoy..:)

Downloading Files in ASP.NET MVC

namespace My.Models

{

    public class DataClasses

    {

        public List<FileNames> GetFiles()

        {

            List<FileNames> lstFiles = new List<FileNames>();

            DirectoryInfo dirInfo = new DirectoryInfo(HostingEnvironment.MapPath("~/Files"));

            int i = 0;

            foreach (var item in dirInfo.GetFiles())

            {

                lstFiles.Add(new FileNames()

                {

                    FileId = i + 1,

                    FileName = item.Name,

                    FilePath = dirInfo.FullName + @"\" + item.Name

                });

                i = i + 1;

            }

            return lstFiles;

        }

    }

    public class FileNames

    {

        public int FileId { get; set; }

        public string FileName { get; set; }

        public string FilePath { get; set; }

    }

}

namespace My.Controllers

{

    public class ReportsController : Controller

    {

        DataClasses objData;

        public ReportsController()

        {

            objData = new DataClasses();

        }

        //

        // GET: /Reports/

        public ActionResult Index()

        {

            var files = objData.GetFiles();

            return View(files);

        }

        public FileResult Download(string id)

        {

            int fid = Convert.ToInt32(id);

            var files = objData.GetFiles();

            string filename = (from f in files

                               where f.FileId == fid

                               select f.FilePath).First();

            string contentType = "application/pdf";

            //Parameters to file are

            //1. The File Path on the File Server

            //2. The content type MIME type

            //3. The parameter for the file save by the browser

            return File(filename, contentType, "Report.pdf");

        }

    }

}

model IEnumerable<my.models.filenames>

    @{

        ViewBag.Title = "Index";

    }

    <h2>Index</h2>

    <p>

        @Html.ActionLink("Create New", "Create")

    </p>

    <table>

        <tr>

            <th>

                FileId

            </th>

            <th>

                FileName

            </th>

        </tr>

        @foreach (var item in Model)

        {

            <tr>

                <td>

                    @Html.DisplayFor(modelItem => item.FileId)

                </td>

                <td>

                    @Html.DisplayFor(modelItem => item.FileName)

                </td>

                <td>

                    @Html.ActionLink("Download", "Download", new { id = item.FileId })

                </td>

            </tr>

        }

    </table>