Data access in mvc using entity framework

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Below is code in EmployeeContext.cs
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using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Data.Entity;

namespace WebApplication2.Models
{
    public class EmployeeContext : DbContext
    {
        public DbSet<Employee> Employees { get; set; }
    }
}

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Below is connectionString in web.config
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  <connectionStrings>
    <add name="EmployeeContext" connectionString="Data Source=localhost;database=Sample;Integrated Security=SSPI"
    providerName="System.Data.SqlClient" />
  </connectionStrings>
  
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Below is code in Employee.cs
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using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Web;

namespace WebApplication2.Models
{
    [Table("tblEmployee")]
    public class Employee
    {
        public int EmployeeId { get; set; }
        public string Name { get; set; }
        public string Gender { get; set; }
        public string City { get; set; }
    }
}

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Below is code in EmployeeController.cs
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using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using WebApplication2.Models;

namespace WebApplication2.Controllers
{
    public class EmployeeController : Controller
    {
        // GET: Employee
        public ActionResult Details(int id)
        {
            EmployeeContext employeeContext = new EmployeeContext();
            Employee employee = employeeContext.Employees.Single(emp => emp.EmployeeId == id);

            return View(employee);
        }
    }
}

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Below is code in Global.asax
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using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Optimization;
using System.Web.Routing;
using System.Data.Entity;

namespace WebApplication2
{
    public class MvcApplication : System.Web.HttpApplication
    {
        protected void Application_Start()
        {
            Database.SetInitializer<WebApplication2.Models.EmployeeContext>(null);
            AreaRegistration.RegisterAllAreas();
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
        }
    }
}