I've added the [Required]
data annotation to one of my models in an ASP.NET MVC application. After creating a migration, running the Update-Database
command results in the following error:
Cannot insert the value NULL into column 'Director', table
'MOVIES_cf7bad808fa94f89afa2e5dae1161e78.dbo.Movies'; column does not
allow nulls. UPDATE fails. The statement has been terminated.
This is due to some records having NULL in their Director
columns. How can I automatically change those values to some default (say "John Doe") director?
Here is my model:
public class Movie
{
public int ID { get; set; }
[Required]
public string Title { get; set; }
[DataType(DataType.Date)]
public DateTime ReleaseDate { get; set; }
[Required]
public string Genre { get; set; }
[Range(1,100)]
[DataType(DataType.Currency)]
public decimal Price { get; set; }
[StringLength(5)]
public string Rating { get; set; }
[Required] /// <--- NEW
public string Director { get; set; }
}
and here is my latest migration:
public partial class AddDataAnnotationsMig : DbMigration
{
public override void Up()
{
AlterColumn("dbo.Movies", "Title", c => c.String(nullable: false));
AlterColumn("dbo.Movies", "Genre", c => c.String(nullable: false));
AlterColumn("dbo.Movies", "Rating", c => c.String(maxLength: 5));
AlterColumn("dbo.Movies", "Director", c => c.String(nullable: false));
}
public override void Down()
{
AlterColumn("dbo.Movies", "Director", c => c.String());
AlterColumn("dbo.Movies", "Rating", c => c.String());
AlterColumn("dbo.Movies", "Genre", c => c.String());
AlterColumn("dbo.Movies", "Title", c => c.String());
}
}
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