Entity Framework

Recipes

  • Generate migration from Package Manager Console

      Add-Migration -Name "MigrationName" -OutputDir "Migrations" -Project EFProj
  Update-Database -Migration "MigrationName" -Project EFProj
  Remove-Migration -Force -Project EFProj

  • multiple column index with OnModelCreating

      class SomeEntityContext : DbContext {
      protected override void OnModelCreating(ModelBuilder modelBuilder) {
          modelBuilder.Entity<MultiKeyIndexEntity>()
                  .HasIndex(u => new { u.Id1, u.Id2, u.SomeReference})
                  .IsUnique();
      }
  }
  • multiple column index by adding a separate migration 
      public partial class OrderTableBrandIdMerchantIdOrderReferenceUniqueIndexAdded : Migration {
          protected override void Up(MigrationBuilder migrationBuilder) {
              migrationBuilder.CreateIndex(
                  name: "IX",
                  table: "SomeTable",
                  columns: new[] { "Id1", "Id2", "SomeReference" },
                  unique: true);
          }

          protected override void Down(MigrationBuilder migrationBuilder) {
              migrationBuilder.DropIndex(
                  name: "IX",
                  table: "SomeTable");
          }
      }

  • A Model Snapshot is the current state of the model stored in a class file named {YourContext}ModelSnapshot.cs

      [DbContext(typeof(SomeEntityContext))]
  partial class ShippingEntityContextModelSnapshot : ModelSnapshot {
      protected override void BuildModel(ModelBuilder modelBuilder) {
          modelBuilder.Entity("EFProj.Models.BusinessEntities.Order", b => {
              b.HasIndex("Id1", "Id2", "SomeReference").IsUnique();
          });
      }
  }
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