Use just the Include extension on IQueryable. It is available in EF 4.1 assembly. If you don’t want to reference that assembly in your upper layers create wrapper extension method in your data access assembly. Here you have example: public static IQueryable<T> IncludeMultiple<T>(this IQueryable<T> query, params Expression<Func<T, object>>[] includes) where T : class { if … Read more
You’re missing the following piece of code after the connectionString attribute (assuming that you’re using SQL): providerName=”System.Data.SqlClient”
I always create another class like ProductImage with a one-to-one association in order to manage lazy loading and also to normalize the table: public class ProductImage { public int ProductId { get; private set; } public byte[] Image { get; set; } }
Just call: something.OrderBy(r => Guid.NewGuid()).Take(5)
In addition to the answer from @webdeveloper and @Pushpendra, you need to manually add updates to your migration to update existing rows. For example: public override void Up() { Sql(“UPDATE [dbo].[Movies] SET Title=”No Title” WHERE Title IS NULL”); AlterColumn(“dbo.Movies”, “Title”, c => c.String(nullable: false,defaultValue:”MyTitle”)); } This is because AlterColumn produces DDL to set the default … Read more
Entity Framework 6 added support for multiple DbContexts by adding the -ContextTypeName and -MigrationsDirectory flags. I just ran the commands in my Package Manager Console and pasted the output below… If you have 2 DbContexts in your project and you run enable-migrations, you’ll get an error (as you probably already know): PM> enable-migrations More than … Read more
You can create computed columns in your database tables. In the EF model you just annotate the corresponding properties with the DatabaseGenerated attribute: [DatabaseGenerated(DatabaseGeneratedOption.Computed)] public double Summ { get; private set; } Or with fluent mapping: modelBuilder.Entity<Income>().Property(t => t.Summ) .HasDatabaseGeneratedOption(DatabaseGeneratedOption.Computed) As suggested by Matija Grcic and in a comment, it’s a good idea to make … Read more
You can also use the Table annotation: [Table(“InternalBlogs”)] public class Blog See: Code First Data Annotations
You can mark both ActivityID and ActivityName properties with Key annotation or you can use fluent API as described by @taylonr. Edit: This should work – composite key defined with annotations requires explicit column order: public class ActivityType { [Key, Column(Order = 0)] public int ActivityID { get; set; } [Key, Column(Order = 1)] [Required(ErrorMessage … Read more
If you have an Order class, adding a property that references another class in your model, for instance Customer should be enough to let EF know there’s a relationship in there: public class Order { public int ID { get; set; } // Some other properties // Foreign key to customer public virtual Customer Customer … Read more