How to use views in Entity Framework?

问题

How can I use database views in Entity Framework?

I have the following view in the SQL database called pl

SELECT dbo.Product.Productkey, 
       dbo.Product.Productcode, 
       dbo.Product.Productname, 
       dbo.rcode.code, 
       dbo.rcode.label 
FROM   dbo.Product 
       INNER JOIN dbo.rcode 
               ON dbo.Product.programtypekey = 
                  dbo.rcode.rcodekey 

How can I read from the above view in application using EF? Currently I am readinmg from a table as shown below. I want to ready from view instead.

In my context, I have

 public virtual DbSet<Product> Product { get; set; }

In Product entity

namespace PDM.Core.App.Data.EF.Entity
{
    public class Product : AuditableEntity<int>
    {
        public int ProgramTypeID { get; set; }
        public string ProductCode { get; set; }
        public string ProductName { get; set; }
}

public class ProductConfiguration : IEntityTypeConfiguration<Product>
{
        public void Configure(EntityTypeBuilder<Product> Product)
        {
            if (Product == null)
                throw new ArgumentNullException(nameof(Product));

            Product.ToTable("Product");
            Product.HasKey(nameof(Product.ID)).HasName("PK_Product");

            Product.Property(p => p.ID)
                .HasColumnName("ProductKey")
                .HasColumnType("int");

            Product.Property(p => p.ProgramTypeID)
                .HasColumnName("ProgramTypeKey")
                .HasColumnType("int")
                .IsRequired(true);

            Product.Property(p => p.ProductCode)
                .HasColumnName("ProductCode")
                .HasColumnType("varchar")
                .HasMaxLength(15)
                .IsRequired(true);

            Product.Property(p => p.ProductName)
                .HasColumnName("ProductName")
                .HasColumnType("varchar")
                .HasMaxLength(50)
                .IsRequired(true);
        }
}

error

回答1:

Firstly, You should create new ProductViewModel to achieve it.

public class ProductViewModel
{
  public string Productkey  { get; set; }
  public string Productcode  { get; set; }
  public string Productname  { get; set; }
  public string rCode  {get; set;}
  public string rLabel  {get; set;}
}

Secondly, Use Join to get 2 tables like below.

var result = await Context.Product.Join(Context.rcode, p => p.programtypekey, c => c.rcodekey, (product, rcode) => 
           new ProductViewModel 
{
  Productkey = product.Productkey ,
  Productcode = product.Productcode,
  Productname = product.Productname,
  rCode = rcode.Code,
  rLabel = rcode.label ,
} 
.AsNoTracking().ToListAsync();

If you want to get data from View, you can achieve it like this way

var result = await Context.Database.SqlQuery<ProductViewModel>("SELECT * FROM dbo.pl ").ToListAsync();

Read the reference from the following post

https://stackoverflow.com/a/18608759/9071943

来源：https://stackoverflow.com/questions/60348462/how-to-use-views-in-entity-framework