Добавил миграции для базы данных storedb

Store/Controllers/ProductController.cs

@@ -52,7 +52,6 @@ namespace Store.Controllers
             return View();
         }
 
-
         [HttpPost]
         public IActionResult Create(Product product)
         {

Store/Migrations/20190530151932_InitialMigration.Designer.cs

+// <auto-generated />
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using Store.Models;
+
+namespace Store.Migrations
+{
+    [DbContext(typeof(ProductContext))]
+    [Migration("20190530151932_InitialMigration")]
+    partial class InitialMigration
+    {
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.SerialColumn)
+                .HasAnnotation("ProductVersion", "2.2.4-servicing-10062")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            modelBuilder.Entity("Store.Models.Product", b =>
+                {
+                    b.Property<string>("Id")
+                        .ValueGeneratedOnAdd();
+
+                    b.Property<int>("Amount");
+
+                    b.Property<string>("Brand");
+
+                    b.Property<string>("Category");
+
+                    b.Property<string>("Name");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Products");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Store/Migrations/20190530151932_InitialMigration.cs

+using Microsoft.EntityFrameworkCore.Migrations;
+
+namespace Store.Migrations
+{
+    public partial class InitialMigration : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "Products",
+                columns: table => new
+                {
+                    Id = table.Column<string>(nullable: false),
+                    Name = table.Column<string>(nullable: true),
+                    Category = table.Column<string>(nullable: true),
+                    Brand = table.Column<string>(nullable: true),
+                    Amount = table.Column<int>(nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_Products", x => x.Id);
+                });
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "Products");
+        }
+    }
+}

Store/Migrations/20190603135845_UpdateProductTable.Designer.cs

+// <auto-generated />
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using Store.Models;
+
+namespace Store.Migrations
+{
+    [DbContext(typeof(ProductContext))]
+    [Migration("20190603135845_UpdateProductTable")]
+    partial class UpdateProductTable
+    {
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.SerialColumn)
+                .HasAnnotation("ProductVersion", "2.2.4-servicing-10062")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            modelBuilder.Entity("Store.Models.Product", b =>
+                {
+                    b.Property<string>("Id")
+                        .ValueGeneratedOnAdd();
+
+                    b.Property<int>("Amount");
+
+                    b.Property<string>("Brand");
+
+                    b.Property<string>("Category");
+
+                    b.Property<string>("Description");
+
+                    b.Property<string>("Name");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Products");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Store/Migrations/20190603135845_UpdateProductTable.cs

+using Microsoft.EntityFrameworkCore.Migrations;
+
+namespace Store.Migrations
+{
+    public partial class UpdateProductTable : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<string>(
+                name: "Description",
+                table: "Products",
+                nullable: true);
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropColumn(
+                name: "Description",
+                table: "Products");
+        }
+    }
+}

Store/Migrations/ProductContextModelSnapshot.cs

+// <auto-generated />
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using Store.Models;
+
+namespace Store.Migrations
+{
+    [DbContext(typeof(ProductContext))]
+    partial class ProductContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("Npgsql:ValueGenerationStrategy", NpgsqlValueGenerationStrategy.SerialColumn)
+                .HasAnnotation("ProductVersion", "2.2.4-servicing-10062")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            modelBuilder.Entity("Store.Models.Product", b =>
+                {
+                    b.Property<string>("Id")
+                        .ValueGeneratedOnAdd();
+
+                    b.Property<int>("Amount");
+
+                    b.Property<string>("Brand");
+
+                    b.Property<string>("Category");
+
+                    b.Property<string>("Description");
+
+                    b.Property<string>("Name");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("Products");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Store/Models/Product.cs

@@ -7,5 +7,6 @@ namespace Store.Models
         public string Category { get; set; }
         public string Brand { get; set; }
         public int Amount { get; set; }
+        public string Description { get; set; }
     }
 }

Store/Models/ProductContext.cs

+using Microsoft.EntityFrameworkCore;
+
+namespace Store.Models
+{
+    public class ProductContext : DbContext
+    {
+        public DbSet<Product> Products { get; set; }
+
+        public ProductContext(DbContextOptions<ProductContext> options) :
+            base(options)
+        {
+
+        }
+    }
+}

Store/Startup.cs

-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading.Tasks;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Http;
-using Microsoft.AspNetCore.HttpsPolicy;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
+using Store.Models;
 
 namespace Store
 {
@@ -31,6 +28,8 @@ namespace Store
                 options.MinimumSameSitePolicy = SameSiteMode.None;
             });
 
+            string connection = Configuration.GetConnectionString("StoreConnection");
+            services.AddDbContext<ProductContext>(options => options.UseNpgsql(connection));
 
             services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
         }

Store/Store.csproj

@@ -6,11 +6,16 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="EntityFramework" Version="6.1.3" />
     <PackageReference Include="Microsoft.AspNetCore" Version="2.1.2" />
     <PackageReference Include="Microsoft.AspNetCore.CookiePolicy" Version="2.1.1" />
     <PackageReference Include="Microsoft.AspNetCore.HttpsPolicy" Version="2.1.1" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="2.1.1" />
     <PackageReference Include="Microsoft.AspNetCore.StaticFiles" Version="2.1.1" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="2.2.4" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="2.2.4" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="2.2.4" />
+    <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="2.2.4" />
   </ItemGroup>
 
   <ItemGroup>

Store/appsettings.json

 {
+  "ConnectionStrings": {
+    "StoreConnection": "Host=localhost;Database=storedb;Username=postgres;Password=1qaz@WSX"
+ },
   "Logging": {
     "LogLevel": {
       "Default": "Warning"