Data Seeding with EF Core

2019-03-17T15:53:01+01:00

I like to thank you for this post. I’ve been searching for many ways to do this, but only with your example I could resolve my issue.

2019-03-17T16:22:13+01:00

Thiago, you’re welcome. Thanks for the feedback.

	public class BooksContext : DbContext
	{
	private const string ConnectionString = @"server=(localdb)\MSSQLLocalDb;database=Books1;trusted_connection=true";
	public DbSet<Book> Books { get; set; }
	protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
	{
	base.OnConfiguring(optionsBuilder);
	optionsBuilder.UseSqlServer(ConnectionString)
	.ConfigureWarnings(warnings => warnings.Throw(RelationalEventId.QueryClientEvaluationWarning));
	}

	protected override void OnModelCreating(ModelBuilder modelBuilder)
	{
	base.OnModelCreating(modelBuilder);

	modelBuilder.Entity<Book>().Property(b => b.Title)
	.IsRequired()
	.HasMaxLength(50);
	modelBuilder.Entity<Book>().Property(b => b.Publisher)
	.IsRequired(false)
	.HasMaxLength(30);

	modelBuilder.Entity<Book>().HasData(
	new Book { BookId = 1, Title = "Professional C# 6", Publisher = "Wrox Press"},
	new Book { BookId = 2, Title = "Professional C# 7", Publisher = "Wrox Press"},
	new Book { BookId = 3, Title = "Professional C# 8", Publisher = "Wrox Press"}
	);
	}
	}

	public class MenuItem
	{
	public int MenuItemId { get; set; }
	public string Text { get; set; }
	[DataType(DataType.Date)]
	public DateTime MenuDate { get; set; }
	}

	protected override void OnModelCreating(ModelBuilder modelBuilder)
	{
	// shadow state
	modelBuilder.Entity<MenuItem>().Property<DateTime>(LastUpdated);

	modelBuilder.Entity<MenuItem>().Property(m => m.Text).IsRequired().HasMaxLength(40);

	// use anonymous types to pass shadow state information
	modelBuilder.Entity<MenuItem>().HasData(
	new { MenuItemId = 1, Text = "Wiener Schnitzel mit Kartoffelsalat", MenuDate = new DateTime(2018, 8, 27), LastUpdated = DateTime.Now },
	new { MenuItemId = 2, Text = "Faschierter Braten mit Karoffelpüree", MenuDate = new DateTime(2018, 8, 28), LastUpdated = DateTime.Now });
	}

	protected override void OnModelCreating(ModelBuilder modelBuilder)
	{
	base.OnModelCreating(modelBuilder);

	modelBuilder.Entity<Racer>().Property(r => r.Name)
	.IsRequired()
	.HasMaxLength(100);
	modelBuilder.Entity<Racer>().Property(r => r.Team)
	.IsRequired(false)
	.HasMaxLength(60);

	modelBuilder.Entity<Racer>().HasData(
	new Racer { Id = 1, Name = "Lewis Hamilton", Team = "Mercedes" },
	new Racer { Id = 2, Name = "Sebastian Vettel", Team = "Ferrari" },
	new Racer { Id = 3, Name = "Kimi Räikkönen", Team = "Ferrari" },
	new Racer { Id = 4, Name = "Valtteri Bottas", Team = "Mercedes" },
	new Racer { Id = 5, Name = "Max Verstappen", Team = "Red Bull Racing"},
	new Racer { Id = 6, Name = "Daniel Ricciardo", Team = "Red Bull Racing"}
	);
	}

	protected override void Up(MigrationBuilder migrationBuilder)
	{
	migrationBuilder.CreateTable(
	name: "Racers",
	columns: table => new
	{
	Id = table.Column<int>(nullable: false)
	.Annotation("SqlServer:ValueGenerationStrategy", SqlServerValueGenerationStrategy.IdentityColumn),
	Name = table.Column<string>(maxLength: 100, nullable: false),
	Team = table.Column<string>(maxLength: 60, nullable: true)
	},
	constraints: table =>
	{
	table.PrimaryKey("PK_Racers", x => x.Id);
	});

	migrationBuilder.InsertData(
	table: "Racers",
	columns: new[] { "Id", "Name", "Team" },
	values: new object[,]
	{
	{ 1, "Lewis Hamilton", "Mercedes" },
	{ 2, "Sebastian Vettel", "Ferrari" },
	{ 3, "Kimi Räikkönen", "Ferrari" },
	{ 4, "Valtteri Bottas", "Mercedes" },
	{ 5, "Max Verstappen", "Red Bull Racing" },
	{ 6, "Daniel Ricciardo", "Red Bull Racing" }
	});
	}

Seeding Data in OnModelCreated

	using (var context = new BooksContext())
	{
	bool created = context.Database.EnsureCreated();
	Console.WriteLine($"Books database created and seeded: {created}");
	}

	private static void SeedWithMigrations()
	{
	using (var context = new F1Context())
	{
	context.Database.Migrate();
	Console.WriteLine("F1 database created, seeded, and updated");
	}
	}

	public partial class AddPoints : Migration
	{
	protected override void Up(MigrationBuilder migrationBuilder)
	{
	migrationBuilder.AddColumn<int>(
	name: "Points",
	table: "Racers",
	nullable: false,
	defaultValue: 0);

	migrationBuilder.UpdateData(
	table: "Racers",
	keyColumn: "Id",
	keyValue: 1,
	column: "Points",
	value: 231);

	migrationBuilder.UpdateData(
	table: "Racers",
	keyColumn: "Id",
	keyValue: 2,
	column: "Points",
	value: 214);

	migrationBuilder.UpdateData(
	table: "Racers",
	keyColumn: "Id",
	keyValue: 3,
	column: "Points",
	value: 146);

	migrationBuilder.UpdateData(
	table: "Racers",
	keyColumn: "Id",
	keyValue: 4,
	column: "Points",
	value: 144);

	migrationBuilder.UpdateData(
	table: "Racers",
	keyColumn: "Id",
	keyValue: 5,
	column: "Points",
	value: 120);

	migrationBuilder.UpdateData(
	table: "Racers",
	keyColumn: "Id",
	keyValue: 6,
	column: "Points",
	value: 118);
	}

	protected override void Down(MigrationBuilder migrationBuilder)
	{
	migrationBuilder.DropColumn(
	name: "Points",
	table: "Racers");
	}
	}