How to add a composite unique key using EF 6 Fluent Api?

Question

I have a table (Id, name, itemst, otherproperties), Id is the primary key and I want a unique composite key (name, itemst). How can I add this using code first either by flu

Answer 1

Let say you have a entity named

public class MyTable
{
    public int Id {get; set;}
    public String Name {get; set;}

}

you can create composite key using

public class YourContext : DbContext
{
    public DbSet MyTables { get; set; }

    protected override void OnModelCreating(DbModelBuilder builder)
    {
        builder.Entity().HasKey(table => new {table.Id, table.Name});
    }
}

if you prefer data annotation you can simple add KeyAttribute to multiple properties

public class MyTable
{
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]  // optional
    [Key]
    public int Id { get; set; }

    [DatabaseGenerated(DatabaseGeneratedOption.None)]   // optional
    [Key]
    public String Name { get; set; }

}