static void Main(string[] args) { ExecuteDDL(); using (var db = new ItemCatalog()) { var member = new Member { Name = "thinkAmi", Address = "SQLite" }; db.Members.Add(member); var item = new Item { Name = "シナノゴールド", Member = member }; db.Items.Add(item); // これを入れるとエラーになる //var item2 = new Item //{ // Name = "hoge", // MemberId = 3 //}; //db.Items.Add(item2); int recordAffected = db.SaveChanges(); db.Items.Select(i => i).ToList().ForEach(row => Console.WriteLine("Id: {0}, Name: {1}, Member Name: {2}, Address: {3}", row.Id, row.Name, row.Member.Name, row.Member.Address)); Console.ReadKey(); } }