// @nuget: EntityFramework

// @nuget: Z.EntityFramework.Extensions

​

using System;

using System.Data.Entity;

using System.Linq;

public class Program

{

    public static void Main()

    {   

        // SEED  

        using (var context = new EntityContext())

        {

            context.GroupMemberships.Add(new GroupMembership { ArchivedDate = DateTime.Now, Changed =  false, EntryStamp =  DateTime.Now});

​

            context.GroupMemberships.Add(new GroupMembership { Changed = false , EntryStamp =  DateTime.Now});

​

            context.SaveChanges();

        }

        using (var context = new EntityContext())

        {

            FiddleHelper.WriteTable("Data Before Update", context.GroupMemberships.ToList());

        }

​

        // TEST  

        using (var context = new EntityContext())

        {

            var groupIds = context.GroupMemberships.Select(x => x.Id).ToList();

            context.GroupMemberships

                .Where(x => !x.ArchivedDate.HasValue && groupIds.Contains(x.Id))

                .UpdateFromQuery(x => new GroupMembership() { Changed = true });

        }

        using (var context = new EntityContext())

        {

            FiddleHelper.WriteTable("Data After Update", context.GroupMemberships.ToList());

        }

    }

​

    public class EntityContext : DbContext

    {

        public EntityContext() : base(FiddleHelper.GetConnectionStringSqlServer())

        {

        }

​

        public DbSet<GroupMembership> GroupMemberships { get; set; }

    }

    public class GroupMembership

    {

        public int Id { get; set; }

        public int GroupId { get; set; }

        public int UserId { get; set; }

        public bool Changed { get; set; }

        public System.DateTime EntryStamp { get; set; }

        public Nullable<System.DateTime> ArchivedDate { get; set; }

    }

}