ASP .NET CORE Sequences

class MyContext : DbContext
{
    public DbSet<Order> Orders { get; set; }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.HasSequence<int>("OrderNumbers");
    }
}

public class Order
{
    public int OrderId { get; set; }
    public int OrderNo { get; set; }
    public string Url { get; set; }
}

As mysql don't have funtion 'Sequences'

so we need to Create a table to stored Sequences 

just as the article below

http://blog.csdn.net/chenaini119/article/details/51993211