See example:

using (var session = Session.Open(domain))
            {
                using (state.Attach(session))
                {
                    using (var transactionScope = Transaction.Open())
                    {
                        using (state.Connect())
                        {
var qwe = Query.All<User>().Select(u => new { u.Created }).ToList();
//Exception here
var aaa = Query.All<User>().ToList();
                        }

                        transactionScope.Complete();
                    }
                }
            }

Version of entity with key 'User, (07f0df2a-b55f-44be-bb9b-034a875bf0de)' differs from the expected one. at Xtensive.Storage.DisconnectedState.RegisterState(Key key, Tuple tuple, VersionInfo version, MergeMode mergeMode) at Xtensive.Storage.DisconnectedState.RegisterState(Key key, Tuple tuple) at Xtensive.Storage.Disconnected.DisconnectedSessionHandler.RegisterEntityState(Key key, Tuple tuple) at Xtensive.Storage.Linq.Materialization.ItemMaterializationContext.Materialize(Int32 entityIndex, Int32 typeIdIndex, TypeInfo type, Pair1[] entityColumns, Tuple tuple) at lambda_method(ExecutionScope , Object[] , Tuple , ItemMaterializationContext ) at System.DelegateBindExtensions.<>c__DisplayClassa4.<bind>b9(T2 arg2, T3 arg3) at Xtensive.Storage.Linq.Materialization.MaterializationHelper.<>cDisplayClass41.<Materialize>b__3(Tuple tuple) at System.Linq.Enumerable.WhereSelectEnumerableIterator2.MoveNext() at System.EnumerableExtensions.<batch>d271.MoveNext() at System.EnumerableExtensions.<ApplyBeforeAndAfter>d__2f1.MoveNext() at Xtensive.Storage.TransactionalExtensions.<totransactional>d01.MoveNext() at System.Linq.Enumerable.<SelectManyIterator>d__142.MoveNext() at System.Collections.Generic.List1..ctor(IEnumerable1 collection) at System.Linq.Enumerable.ToListTSource at Core.Tests.MembershipTest.SomeMethod() in D:\Home\Docs\Visual Studio 2008\Projects\Platform\Core.Tests\MembershipTest.cs:line 93

Updated at 02.04.2010 11:46:16

var state = new DisconnectedState();

            using (var session = Session.Open(domain))
            {
                using (state.Attach(session))
                {
                    using (var transactionScope = Transaction.Open())
                    {
                        using (state.Connect())
                        {
                            //SomeMethod();
                            var doc = Query.All<FilterEntity>().Where(f => f.Integer == 1).Prefetch(s => s.ItemGroup).Single();
                            var qwe = Query.All<User>().Select(u => new { u.Created }).ToList();

                            var subs = doc.ItemGroup.Where(g => true).ToList();

                            foreach (var sub in subs)
                            {
                                sub.Name = "1111";
                            }

                            doc.ItemGroup.Add(new AnotherEntity(Guid.NewGuid()));
                            doc.ItemGroup.Add(new AnotherEntity(Guid.NewGuid()));
                            doc.ItemGroup.Add(new AnotherEntity(Guid.NewGuid()));

                            var uuu = Query.All<User>().Select(u => new { u.Created }).OrderBy(a => a.Created).First();
                        }

                        var fe = new FilterEntity(Guid.NewGuid()) { Date = DateTime.Now, Integer = 123 };
                        //var ss = Query.All<FilterEntity>().Where(f => f.NullableGuid.HasValue).Single();
                        fe.Integer = 2222;

                        transactionScope.Complete();
                    }
                }
            }

            using (var session = Session.Open(domain))
            {
                using (state.Attach(session))
                {
                    using (var transactionScope = Transaction.Open())
                    {
                        using (state.Connect())
                        {
                            // Exception here
                            var doc = Query.All<FilterEntity>().Where(f => f.Integer == 1).Prefetch(s => s.ItemGroup).Single();

                            var subs = doc.ItemGroup.Where(g => true).ToList();

                            foreach (var sub in subs)
                            {
                                sub.Name = "22222";
                            }
                        }

                        transactionScope.Complete();
                    }
                }

                state.ApplyChanges();
            }

More exceptions here

Xtensive.Storage.VersionConflictException : Version of entity with key 'AnotherEntity, (0df4b47f-e104-42cf-adce-85da7a5e80c4)' differs from the expected one. at Xtensive.Storage.DisconnectedState.RegisterState(Key key, Tuple tuple, VersionInfo version, MergeMode mergeMode) at Xtensive.Storage.DisconnectedState.RegisterState(Key key, Tuple tuple) at Xtensive.Storage.Disconnected.DisconnectedSessionHandler.RegisterEntityState(Key key, Tuple tuple) at Xtensive.Storage.Internals.Prefetch.EntitySetTask.UpdateCache() at Xtensive.Storage.Internals.Prefetch.Fetcher.UpdateCacheFromAllEntitySetTasks(IEnumerable1 containers) at Xtensive.Storage.Internals.Prefetch.Fetcher.ExecuteTasks(IEnumerable1 containers, Boolean skipPersist) at Xtensive.Storage.Internals.Prefetch.PrefetchManager.ExecuteTasks(Boolean skipPersist) at Xtensive.Storage.Providers.SessionHandler.ExecutePrefetchTasks(Boolean skipPersist) at Xtensive.Storage.Internals.ChainingSessionHandler.ExecutePrefetchTasks(Boolean skipPersist) at Xtensive.Storage.Internals.Prefetch.RootElementsPrefetcher1.<GetEnumerator>d__0.MoveNext() at System.Linq.Enumerable.Single(IEnumerable1 source) at Core.Tests.MembershipTest.DsTest() in MembershipTest.cs: line 112

Updated at 02.04.2010 12:45:11

> Have a look at the first example. There are sequential Query.All() calls. No data is being modified. But it isn't clear if DisconnectedState is empty before this operation. Is it? It was empty, trust me :)

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