Required attribute can be applied to a property of a domain class. EF Code-First will create a NOT NULL column in a database table for a property on which we apply Required attribute. Note that it can also be used with ASP.Net MVC as a validation attribute.

Consider the following example.

using System.ComponentModel.DataAnnotations;

public class Student
{
public Student()
{ }
public int StudentID { get; set; } [Required]
public string StudentName { get; set; } }

As you can see in the above code, we have applied Required attribute to StudentName. So, Code First will create a NOT NULL StudentName column in the Student table as shown below.

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