Add the [`[System.ComponentModel.DataAnnotations.Schema.NotMapped]`](http://msdn.microsoft.com/en-us/library/system.componentmodel.dataannotations.schema.notmappedattribute.aspx) attribute to the property.

Per the [accepted answer](https://stackoverflow.com/a/10572463/1037948) and [similar question/answer](https://stackoverflow.com/a/10385738/1037948), in addition to `[NotMapped]` you can also specify it using the Fluent API:

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
       modelBuilder.Entity&lt;TheModelAffected&gt;().Ignore(t =&gt; t.TheIgnoredProperty);
       base.OnModelCreating(modelBuilder);
    }

`[NotMapped]` is the short version if you like conciseness. And of course, you would add:

    using System.ComponentModel.DataAnnotations.Schema;
to your class.

Is allocating a buffer via `new char[sizeof(T)]` guaranteed to allocate memory which is properly aligned for the type `T`, where all members of `T` has their natural, implementation defined, alignment (that is, you have not used the `alignas` keyword to modify their alignment).

I have seen this guarantee made in a few answers around here but I&#39;m not entirely clear how the standard arrives at this guarantee.  5.3.4-10 of the standard gives the basic requirement: essentially `new char[]` must be aligned to `max_align_t`.

What I&#39;m missing is the bit which says `alignof(T)` will always be a valid alignment with a maximum value of `max_align_t`. I mean, it seems obvious, but must the resulting alignment of a structure be at most `max_align_t`? Even point 3.11-3 says extended alignments may be supported, so may the compiler decide on its own a class is an over-aligned type?


Does new char actually guarantee aligned memory for a class type?

I just started using Maven and I read that plugins are additional components that can be used.   
A typical structure of `pom.xml` file is

&lt;!-- language: xml-lang --&gt;

    &lt;project&gt;
      &lt;groupId&gt;org.koshik.javabrains&lt;/groupId&gt;
      &lt;artifactId&gt;JarName&lt;/artifactId&gt; (A fldernamed JarName was created) 
      &lt;version&gt;1.0-SNAPSHOT&lt;/version&gt;
      &lt;packaging&gt;jar&lt;/packaging&gt;
    
      &lt;name&gt;JarName&lt;/name&gt;
      &lt;url&gt;http://maven.apache.org&lt;/url&gt;
    
      &lt;properties&gt;
        &lt;project.build.sourceEncoding&gt;UTF-8&lt;/project.build.sourceEncoding&gt;
      &lt;/properties&gt;
    
      &lt;dependencies&gt;
        &lt;dependency&gt;
          &lt;groupId&gt;junit&lt;/groupId&gt;
          &lt;artifactId&gt;junit&lt;/artifactId&gt;
          &lt;version&gt;3.8.1&lt;/version&gt;
          &lt;scope&gt;test&lt;/scope&gt;
        &lt;/dependency&gt;
      &lt;/dependencies&gt;
    &lt;/project&gt;

**Question**: Where should I insert a `plugin` tag? such as the following:

    &lt;plugin&gt;
      &lt;groupId&gt;org.jibx&lt;/groupId&gt;
      &lt;artifactId&gt;jibx-maven-plugin&lt;/artifactId&gt;
      &lt;version&gt;1.2.4&lt;/version&gt;
      &lt;executions&gt;
        &lt;execution&gt;
          &lt;goals&gt;
            &lt;goal&gt;bind&lt;/goal&gt;
          &lt;/goals&gt;
        &lt;/execution&gt;
      &lt;/executions&gt;
    &lt;/plugin&gt;

Before the dependency or after the `dependency` tag? Does it matter?

Plugins in Maven and POM.xml

Entity Framework Code First will auto-create a table in the database base based on the Model.

Is there an attribute that will avoid this?

How to ignore a property when using Entity Framework Code First

<p>Entity Framework Code First will auto-create a table in the database base based on the Model.</p>
<p>Is there an attribute that will avoid this?</p>


I have been reading a lot of articles explaining how to set up Entity Framework&#39;s `DbContext` so that only one is created and used per HTTP web request using various DI frameworks.

Why is this a good idea in the first place? What advantages do you gain by using this approach? Are there certain situations where this would be a good idea? Are there things that you can do using this technique that you can&#39;t do when instantiating `DbContext`s per repository method call?



One DbContext per web request... why?

I am using Entity Framework 4.3 and using Code Fist.

I have a class 

    public class User
    {
       public int UserId{get;set;}
       public string UserName{get;set;}
    }

How do I tell Entity Framework that UserName has to be unique when creating database table?
I would prefer to use data anotations instead of configuration file if possible.


Entity Framework code first unique column

Using the data annotation `Required` like so:

    [Required]
    public int somefield {get; set;}

Will set &lt;b&gt;somefield&lt;/b&gt; to `Not Null` in database, How can I set &lt;b&gt;somefield&lt;/b&gt;
to allow NULLs?, I tried setting it through SQL Server Management Studio but Entity Framework set it back to *`Not Null`*.

Nullable property to entity field, Entity Framework through Code First

The Include() method works quite well for Lists on objects. But what if I need to go two levels deep? For example, the method below will return ApplicationServers with the included properties shown here. However, ApplicationsWithOverrideGroup is another container that holds other complex objects. Can I do an Include() on that property as well? Or how can I get that property to fully load?

**As it stands now, this method:**

    public IEnumerable&lt;ApplicationServer&gt; GetAll()
    {
        return this.Database.ApplicationServers
            .Include(x =&gt; x.ApplicationsWithOverrideGroup)                
            .Include(x =&gt; x.ApplicationWithGroupToForceInstallList)
            .Include(x =&gt; x.CustomVariableGroups)                
            .ToList();
    }

Will populate only the Enabled property (below) and not the Application or CustomVariableGroup properties (below). How do I make this happen?

    public class ApplicationWithOverrideVariableGroup : EntityBase
    {
        public bool Enabled { get; set; }
        public Application Application { get; set; }
        public CustomVariableGroup CustomVariableGroup { get; set; }
    }

Entity Framework - Include Multiple Levels of Properties

I&#39;m just looking into using EF migrations for our project, and in particular for performing schema changes in production between releases. 

I have seen mentioned that there is an API to perform these migrations at run-time using the `DbMigration` class, but I can&#39;t find any specific examples. 

Ideally, I would want one `DbMigration` file for every database change, and for those changes to be applied automatically on application start up from the current version up to the latest version.

Using Entity Framework (code first) migrations in production

I use code-first in my project and deploy on host but I get error

&gt; CREATE DATABASE permission denied in database &#39;master&#39;.

This is my connection string:

    &lt;add name=&quot;DefaultConnection&quot; 
         connectionString=&quot;Data Source=.\SQLEXPRESS;Initial Catalog=aspnet-test-2012615153521;Integrated Security=False&quot; 
         providerName=&quot;System.Data.SqlClient;User ID=test;Password=test&quot;/&gt;

 


CREATE DATABASE permission denied in database &#39;master&#39; (EF code-first)

Is there a way to decorate your POCO classes to automatically eager-load child entities without having to use `Include()` every time you load them? 

Say I have a Class Car, with Complex-typed Properties for Wheels, Doors, Engine, Bumper, Windows, Exhaust, etc. And in my app I need to load my car from my DbContext 20 different places with different queries, etc. I don&#39;t want to have to specify that I want to include all of the properties every time I want to load my car. 

I want to say 

    List&lt;Car&gt; cars = db.Car
                    .Where(x =&gt; c.Make == &quot;Ford&quot;).ToList();
    
    //NOT .Include(x =&gt; x.Wheels).Include(x =&gt; x.Doors).Include(x =&gt; x.Engine).Include(x =&gt; x.Bumper).Include(x =&gt; x.Windows)
    
    
    foreach(Car car in cars)
    {
    
    //I don&#39;t want a null reference here.
    
    String myString = car.**Bumper**.Title;
    }

Can I somehow decorate my POCO class or in my `OnModelCreating()` or set a configuration in EF that will tell it to just load all the parts of my car when I load my car? I want to do this eagerly, so my understanding is that making my navigation properties virtual is out. I know NHibernate supports similar functionality. 

Just wondering if I&#39;m missing something. Thanks in advance!

Cheers,

Nathan


I like the solution below, but **am wondering if I can nest the calls to the extension methods.** For example, say I have a similar situation with Engine where it has many parts I don&#39;t want to include everywhere. Can I do something like this? (I&#39;ve not found a way for this to work yet). This way if later I find out that Engine needs FuelInjectors, I can add it only in the BuildEngine and not have to also add it in BuildCar. **Also if I can nest the calls, how can I nest a call to a collection? Like to call BuildWheel() for each of my wheels from within my BuildCar()?**

    public static IQueryable&lt;Car&gt; BuildCar(this IQueryable&lt;Car&gt; query) {
         return query.Include(x =&gt; x.Wheels).BuildWheel()
                     .Include(x =&gt; x.Doors)
                     .Include(x =&gt; x.Engine).BuildEngine()
                     .Include(x =&gt; x.Bumper)
                     .Include(x =&gt; x.Windows);
    }
    
    public static IQueryable&lt;Engine&gt; BuildEngine(this IQueryable&lt;Engine&gt; query) {
         return query.Include(x =&gt; x.Pistons)
                     .Include(x =&gt; x.Cylendars);
    }

    //Or to handle a collection e.g.
     public static IQueryable&lt;Wheel&gt; BuildWheel(this IQueryable&lt;Wheel&gt; query) {
         return query.Include(x =&gt; x.Rim)
                     .Include(x =&gt; x.Tire);
    }


Here is another very similar thread in case it is helpful to anyone else in this situation, but it still doesn&#39;t handle being able to make nexted calls to the extension methods.

https://stackoverflow.com/questions/3356541/entity-framework-linq-query-include-multiple-children-entities


Entity Framework - Is there a way to automatically eager-load child entities without Include()?

I have a code-first entity model in EF5. But I want to manage the database changes manually -- I do not want EF to modify my existing database and all its data. But when I make parallel changes in the EF mapping and in the database, EF refuses to operate properly telling me I need to use code first migration.  How do I turn this off?

How can I disable code first migrations

I&#39;ve got multiple classes (including TPT) in my project. Each POCO has a `BaseClass`, which has a `GUID` (called `GlobalKey`) as primary key.

First I used `DataAnnotations` to create correct foreign keys. But then I&#39;ve got problems synchronizing the corresponding GUID with the object itself.

Now I want to have only one virtual navigation property so that the GUID field in the database is created by `NamingConvention`. But the field name always adds an underscore followed by the word `GlobalKey` (which is right). When I want to remove the underscore, I don&#39;t want to go thru all my POCOs in the fluent API to do this:

    // Remove underscore from Navigation-Field     
    modelBuilder.Entity&lt;Person&gt;()
                .HasOptional(x =&gt; x.Address)
                .WithMany()
                .Map(a =&gt; a.MapKey(&quot;AddressGlobalKey&quot;));

Any ideas to do this for all POCOS by overwriting a convention?

Thanks in advance.

Andreas


Content Type	Original Author	Original Content on Stackoverflow
Question	Dozer	View Question on Stackoverflow
Solution 1 - Entity Framework	SLaks	View Answer on Stackoverflow
Solution 2 - Entity Framework	drzaus	View Answer on Stackoverflow
Solution 3 - Entity Framework	cyclical	View Answer on Stackoverflow

How to ignore a property when using Entity Framework Code First

Entity Framework Problem Overview

Entity Framework Solutions

Solution 1 - Entity Framework

Solution 2 - Entity Framework

Solution 3 - Entity Framework

Plugins in Maven and POM.xml

Does new char actually guarantee aligned memory for a class type?

Attributions