using System.ComponentModel.DataAnnotations; using System.ComponentModel.DataAnnotations.Schema; using System.Diagnostics.CodeAnalysis; namespace Aufgabe14; [Table("Customers")] public class Customer { [NotNull] // Unterschied Required? [Column(TypeName = "varchar(100)")] public string Firstname { get; set; } [NotNull] // [Column(TypeName = "varchar(100)")] Wie geht das? [Column("Lastname")] public string Surname { get; set; } [Key] public int Id { get; set; } [NotNull] public Gender Gender { get; set; } public Address Address { get; set; } = new Address(); }