Unable to update database to match the current model because there are pending changes and 
automatic migration is disabled. Either write the pending model changes to a code-based migration 
or enable automatic migration. Set DbMigrationsConfiguration.AutomaticMigrationsEnabled to true
to enable automatic migration.

Add-Migration AddSomeProp2ToProject

namespace EF_Sample02.Migrations
{
    using System.Data.Entity.Migrations;
    
    public partial class AddSomeProp2ToProject : DbMigration
    {
        public override void Up()
        {
            AddColumn("Projects", "SomeProp", c => c.String());
            AddColumn("Projects", "SomeProp2", c => c.String());
        }
        
        public override void Down()
        {
            DropColumn("Projects", "SomeProp2");
            DropColumn("Projects", "SomeProp");
        }
    }
}

Update-Database -Verbose

Using NuGet project 'EF_Sample02'.
Using StartUp project 'EF_Sample02'.
Target database is: 'testdb2012' (DataSource: (local), Provider: System.Data.SqlClient, Origin: Configuration).
Applying explicit migrations: [201205061835024_AddSomeProp2ToProject].
Applying explicit migration: 201205061835024_AddSomeProp2ToProject.
ALTER TABLE [Projects] ADD [SomeProp] [nvarchar](max)
ALTER TABLE [Projects] ADD [SomeProp2] [nvarchar](max)
[Inserting migration history record]

Add-Migration AddSomeProp3ToProject
Update-Database -Verbose

get-help update-database -detailed

Update-Database -TargetMigration:"AddSomeProp2ToProject" -Verbose

Using NuGet project 'EF_Sample02'.
Using StartUp project 'EF_Sample02'.
Target database is: 'testdb2012' (DataSource: (local), Provider: System.Data.SqlClient, Origin: Configuration).
Reverting migrations: [201205061845485_AddSomeProp3ToProject].
Reverting explicit migration: 201205061845485_AddSomeProp3ToProject.
DECLARE @var0 nvarchar(128)
SELECT @var0 = name
FROM sys.default_constraints
WHERE parent_object_id = object_id(N'Projects')
AND col_name(parent_object_id, parent_column_id) = 'SomeProp3';
IF @var0 IS NOT NULL
    EXECUTE('ALTER TABLE [Projects] DROP CONSTRAINT ' + @var0)
ALTER TABLE [Projects] DROP COLUMN [SomeProp3]
[Deleting migration history record]

namespace EF_Sample02.Migrations
{
    using System.Data.Entity.Migrations;
    
    public partial class AddSomeProp3ToProject : DbMigration
    {
        public override void Up()
        {
            AddColumn("Projects", "SomeProp3", c => c.String(defaultValue: "some data"));
            Sql("Update Projects set SomeProp3=N'some data'");
        }
        
        public override void Down()
        {
            DropColumn("Projects", "SomeProp3");
        }
    }
}

public ColumnModel String(bool? nullable = null, int? maxLength = null, bool? fixedLength = null, 
bool? isMaxLength = null, bool? unicode = null, string defaultValue = null, string defaultValueSql = null, 
string name = null, string storeType = null)

ALTER TABLE [Projects] ADD [SomeProp3] [nvarchar](max) DEFAULT 'some data'

namespace EF_Sample02.Migrations
{
    using System;
    using System.Data.Entity.Migrations;

    internal sealed class Configuration : DbMigrationsConfiguration<EF_Sample02.Sample2Context>
    {
        public Configuration()
        {
            this.AutomaticMigrationsEnabled = false;
            this.AutomaticMigrationDataLossAllowed = true;
        }

        protected override void Seed(EF_Sample02.Sample2Context context)
        {
            context.Users.AddOrUpdate(
                 a => a.Name,
                 new Models.User { Name = "Vahid", AddDate = DateTime.Now },
                 new Models.User { Name = "Test", AddDate = DateTime.Now });
        }
    }
}

Update-Database -Verbose -Script

ALTER TABLE [Projects] ADD [SomeProp5] [nvarchar](max)
INSERT INTO [__MigrationHistory] ([MigrationId], [CreatedOn], [Model], [ProductVersion]) VALUES 
('201205060852004_AutomaticMigration', '2012-05-06T08:52:00.937Z', 0x1F8B0800000............ '4.3.1')

Update-Database -Verbose -Script -SourceMigration:"stepName"

Add-Migration AddSomePropToProject
Update-Database -Verbose -Script

namespace ProductService.Models
{
    public class ProductRating
    {
        public int ID { get; set; }
        public int Rating { get; set; }
        public int ProductID { get; set; }
        public virtual Product Product { get; set; }  
    }
}

ODataModelBuilder builder = new ODataConventionModelBuilder();
builder.EntitySet<Product>("Products");

builder.Namespace = "ProductService";
builder.EntityType<Product>()
    .Action("Rate")
    .Parameter<int>("Rating");

[HttpPost]
public async Task<IHttpActionResult> Rate([FromODataUri] int key, ODataActionParameters parameters)
{
    if (!ModelState.IsValid)
    {
        return BadRequest();
    }

    int rating = (int)parameters["Rating"];
    db.Ratings.Add(new ProductRating
    {
        ProductID = key,
        Rating = rating
    });

    await db.SaveChangesAsync();
    
    return StatusCode(HttpStatusCode.NoContent);
}

POST http://localhost/Products(1)/ProductService.Rate HTTP/1.1
Content-Type: application/json
Content-Length: 12

{"Rating":5}

HttpClient client = new HttpClient();
var response = client.PostAsync(postUrl, new StringContent(JsonConvert.SerializeObject(new { Rating = 5 }), Encoding.UTF8, "application/json")).Result;

ODataModelBuilder builder = new ODataConventionModelBuilder();
builder.EntitySet<Product>("Products");
builder.EntitySet<Supplier>("Suppliers");

builder.Namespace = "ProductService";
builder.EntityType<Product>().Collection
    .Function("MostExpensive")
    .Returns<double>();

ReturnsFromEntitySet<Product>("Products")

ReturnsCollectionFromEntitySet<Product>("Products");

ReturnsCollection<string>();

GET http://localhost/Products/ProductService.MostExpensive

public class ProductsController : ODataController
{
    [HttpGet]
    public IHttpActionResult MostExpensive()
    {
        var product = db.Products.Max(x => x.Price);
        return Ok(product);
    }

    // Other controller methods not shown.
}

HTTP/1.1 200 OK
Content-Type: application/json; odata.metadata=minimal; odata.streaming=true
OData-Version: 4.0
Date: Sat, 28 Jun 2016 00:44:07 GMT
Content-Length: 85

{
  "@odata.context":"http://localhost:38479/$metadata#Edm.Decimal","value":50.00
}

ODataModelBuilder builder = new ODataConventionModelBuilder();
builder.EntitySet<Product>("Products");

builder.Function("GetSalesTaxRate")
    .Returns<double>()
    .Parameter<int>("PostalCode");

[HttpGet]
[ODataRoute("GetSalesTaxRate(PostalCode={postalCode})")]
public IHttpActionResult GetSalesTaxRate([FromODataUri] int postalCode)
{
    double rate = 5.6;  // Use a fake number for the sample.
    return Ok(rate);
}

GET http://localhost/GetSalesTaxRate(PostalCode=10) HTTP/1.1

HTTP/1.1 200 OK
Content-Type: application/json; odata.metadata=minimal; odata.streaming=true
OData-Version: 4.0
Date: Sat, 28 Jun 2016 01:05:32 GMT
Content-Length: 82

{
  "@odata.context":"http://localhost:38479/$metadata#Edm.Double","value":5.6
}

@{
    ViewBag.Title = "Index";
}
<h2>
    Index</h2>
<fieldset>
    <legend>HandleForm1 (Normal)</legend>
    @using (Html.BeginForm(actionName: "HandleForm1", controllerName: "Home"))
    {
        @:your favorite tech: <br />
        @Html.RadioButton(name: "tech", value: ".NET", isChecked: true) @:DOTNET <br />
        @Html.RadioButton(name: "tech", value: "JAVA", isChecked: false) @:JAVA <br />
        @Html.RadioButton(name: "tech", value: "PHP", isChecked: false) @:PHP <br />
        <input type="submit" value="Submit" />
    }
</fieldset>

using System.Collections.Generic;
using System.Web.Mvc;

namespace MvcApplication23.Controllers
{
    public class HomeController : Controller
    {
        [HttpGet]
        public ActionResult Index()
        {
            return View();
        }

        [HttpPost]
        public ActionResult HandleForm1(string tech)
        {
            return RedirectToAction("Index");
        }
    }
}

@helper RadioButtonList(string groupName, IEnumerable<System.Web.Mvc.SelectListItem> items)
{
    <div class="RadioButtonList">
        @foreach (var item in items)
        {
            @item.Text
            <input type="radio" name="@groupName"
                   value="@item.Value"
                   @if (item.Selected) { <text>checked="checked"</text> }
               />
            <br />
        }
    </div>
}

using System.Collections.Generic;
using System.Web.Mvc;

namespace MvcApplication23.Controllers
{
    public class HomeController : Controller
    {
        [HttpGet]
        public ActionResult Index()
        {
            ViewBag.Tags = new[]
                            {
                                new SelectListItem { Text = ".NET", Value = "Val1", Selected = true },
                                new SelectListItem { Text = "JAVA", Value = "Val2", Selected = false },
                                new SelectListItem { Text = "PHP", Value = "Val3", Selected = false }
                            };
            return View();
        }

        [HttpPost]
        public ActionResult HandleForm2(string preferredTechnology)
        {
            return RedirectToAction("Index");
        }
    }
}

@{
    ViewBag.Title = "Index";
}
<h2>
    Index</h2>

<fieldset>
    <legend>HandleForm2 (Helper)</legend>
    @using (Html.BeginForm(actionName: "HandleForm2", controllerName: "Home"))
    {
        @:your favorite tech: <br />
        @Helpers.RadioButtonList("preferredTechnology", (SelectListItem[])ViewBag.Tags)
        <input type="submit" value="Submit" />
    }
</fieldset>

using System.ComponentModel.DataAnnotations;

namespace MvcApplication23.Models
{
    public enum Gender
    {
        [Display(Name = "مرد")]
        Male,
        [Display(Name = "زن")]
        Female,
    }

    public class User
    {
        [ScaffoldColumn(false)]
        public int Id { set; get; }

        [Display(Name = "نام")]
        public string Name { set; get; }

        [Display(Name = "جنسیت")]
        [UIHint("EnumRadioButtonList")]
        public Gender Gender { set; get; }
    }
}

@using System.ComponentModel.DataAnnotations
@using System.Globalization
@model Enum
@{
    Func<Enum, string> getDescription = enumItem =>
    {
        var type = enumItem.GetType();
        var memInfo = type.GetMember(enumItem.ToString());
        if (memInfo != null && memInfo.Any())
        {
            var attrs = memInfo[0].GetCustomAttributes(typeof(DisplayAttribute), false);
            if (attrs != null && attrs.Any())
                return ((DisplayAttribute)attrs[0]).GetName();
        }
        return enumItem.ToString();
    };

    var listItems = Enum.GetValues(Model.GetType())
                        .OfType<Enum>()
                        .Select(enumItem =>
                                    new SelectListItem()
                                    {
                                        Text = getDescription(enumItem),
                                        Value = enumItem.ToString(),
                                        Selected = enumItem.Equals(Model)
                                    });

    string prefix = ViewData.TemplateInfo.HtmlFieldPrefix;    
    ViewData.TemplateInfo.HtmlFieldPrefix = string.Empty;

    int index = 0;
    foreach (var li in listItems)
    {
        string fieldName = string.Format(CultureInfo.InvariantCulture, "{0}_{1}", prefix, index++);
    <div class="editor-radio">
        @Html.RadioButton(prefix, li.Value, li.Selected, new { @id = fieldName })
        @Html.Label(fieldName, li.Text)
    </div>
    }

    ViewData.TemplateInfo.HtmlFieldPrefix = prefix;
}

using System.Collections.Generic;
using System.Web.Mvc;
using MvcApplication23.Models;

namespace MvcApplication23.Controllers
{
    public class HomeController : Controller
    {
        [HttpGet]
        public ActionResult Index()
        {
            var user = new User { Id = 1, Name = "name 1", Gender = Gender.Male };
            return View(user);
        }

        [HttpPost]
        public ActionResult HandleForm3(User user)
        {
            return RedirectToAction("Index");
        }
    }
}

@model MvcApplication23.Models.User
@{
    ViewBag.Title = "Index";
}
<h2>
    Index</h2>
<fieldset>
    <legend>HandleForm3 (EditorForModel)</legend>
    @using (Html.BeginForm(actionName: "HandleForm3", controllerName: "Home"))
    {
        @Html.EditorForModel()
        <input type="submit" value="Submit" />
    }
</fieldset>

@Html.EditorFor(model => model.EnumProperty, "EnumRadioButtonList")