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  • using Autofac in a multi-layered architecture

    - by Kamyar
    I'm fairly new to the DI/IoC concept and would like to use Autofac in a 3-layered ASP.NET Webforms application. UI layer: An ASP.NET webforms website. BLL: Business logic layer which calls the repositories on DAL. DAL: .EDMX file (Entity Model) and ObjectContext with Repository classes which abstract the CRUD operations for each entity. Entities: The POCO Entities. Persistence Ignorant. Generated by Microsoft's ADO.Net POCO Entity Generator. I have asked a more general question here. Basically, I'd like to create an obejctcontext per HttpContext in my DAL. But i don't want to add a reference to DAL in UI or access to HttpContext in DAL directly. I guess this is where IoC tools come to play. The answer to my previous question is a very good example of using Windsor Castle. I'd like to use Autofac as my IoC tool and Don't know how to achieve this. (How to access DAL in application_start to register the component while I don't want to reference it in my UI, what are the proper references to be able to use DAL component in BLL with Autofac, Should I register BLL as a component with Autofac too) Sorry folks for not providing an explicit question and requesting a kind of working example, But I'm very unfamiliar to the whole IoC concept and I don't think I can achieve it to use in my current time-limited project.

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  • How to fluent-map this (using fluent nhibernate)?

    - by vikasde
    I have two tables in my database "Styles" and "BannedStyles". They have a reference via the ItemNo. Now styles can be banned per store. So if style x is banned at store Y then its very possible that its not banned at store Z or vice verse. What is the best way now to map this to a single entity? Should I be mapping this to a single entity? My Style entity looks like this: public class Style { public virtual int ItemNo { get; set;} public virtual string SKU { get; set; } public virtual string StyleName { get; set; } public virtual string Description { get; set; } public virtual Store Store { get; set; } public virtual bool IsEntireStyleBanned { get; set; } }

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  • How to use the LINQ where expression?

    - by NullReference
    I'm implementing the service \ repository pattern in a new project. I've got a base interface that looks like this. Everything works great until I need to use the GetMany method. I'm just not sure how to pass a LINQ expression into the GetMany method. For example how would I simply sort a list of objects of type name? nameRepository.GetMany( ? ) public interface IRepository<T> where T : class { void Add(T entity); void Update(T entity); void Delete(T entity); void Delete(Expression<Func<T, bool>> where); T GetById(long Id); T GetById(string Id); T Get(Expression<Func<T, bool>> where); IEnumerable<T> GetAll(); IEnumerable<T> GetMany(Expression<Func<T, bool>> where); } public virtual IEnumerable<T> GetMany(Expression<Func<T, bool>> where) { return dbset.Where(where).ToList(); }

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  • Organizing Eager Queries in an ObjectContext

    - by Nix
    I am messing around with Entity Framework 3.5 SP1 and I am trying to find a cleaner way to do the below. I have an EF model and I am adding some Eager Loaded entities and i want them all to reside in the "Eager" property in the context. We originally were just changing the entity set name, but it seems a lot cleaner to just use a property, and keep the entity set name in tact. Example: Context - EntityType - AnotherType - Eager (all of these would have .Includes to pull in all assoc. tables) - EntityType - AnotherType Currently I am using composition but I feel like there is an easier way to do what I want. namespace Entities{ public partial class TestObjectContext { EagerExtensions Eager { get;set;} public TestObjectContext(){ Eager = new EagerExtensions (this); } } public partial class EagerExtensions { TestObjectContext context; public EagerExtensions(TestObjectContext _context){ context = _context; } public IQueryable<TestEntity> TestEntity { get { return context.TestEntity .Include("TestEntityType") .Include("Test.Attached.AttachedType") .AsQueryable(); } } } } public class Tester{ public void ShowHowIWantIt(){ TestObjectContext context= new TestObjectContext(); var query = from a in context.Eager.TestEntity select a; } }

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  • How can I have 2 ADO access methods use the same Transaction?

    - by KevinDeus
    I'm writing a test to see if my LINQ to Entity statement works.. I'll be using this for others if I can get this concept going.. my intention here is to INSERT a record with ADO, then verify it can be queried with LINQ, and then ROLLBACK the whole thing at the end. I'm using ADO to insert because I don't want to use the object or the entity model that I am testing. I figure that a plain ADO INSERT should do fine. problem is.. they both use different types of connections. is it possible to have these 2 different data access methods use the same TRANSACTION so I can roll it back?? _conn = new SqlConnection(_connectionString); _conn.Open(); _trans = _conn.BeginTransaction(); var x = new SqlCommand("INSERT INTO Table1(ID, LastName, FirstName, DateOfBirth) values('127', 'test2', 'user', '2-12-1939');", _conn); x.ExecuteNonQuery(); //So far, so good. Adding a record to the table. //at this point, we need to do **_trans.Commit()** here because our Entity code can't use the same connection. Then I have to manually delete in the TestHarness.TearDown.. I'd like to eliminate this step //(this code is in another object, I'll include it for brevity. Imagine that I passed the connection in) //check to see if it is there using (var ctx = new XEntities(_conn)) //can't do this.. _conn is not an EntityConnection! { var retVal = (from m in ctx.Table1 where m.first_name == "test2" where m.last_name == "user" where m.Date_of_Birth == "2-12-1939" where m.ID == 127 select m).FirstOrDefault(); return (retVal != null); } //Do test.. Assert.BlahBlah(); _trans.Rollback();

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  • Mapping one column in a table to multiple tables

    - by user1721814
    I am working on a new product development creating a WMS system. I have done it in past using ASP, VB, and other techniques where we did not hard code the mapping. But now i am working on it using MVC and entity frame work and i am stumped. How can i map one column in transaction table to a column in multiple tables. I have transaction table trans Transid orderref TType productid qty ....(More Columns) now the orderref will hold either Receiptkey, orderkey , movementkey, adjustmentkey and the TType column will tell me which type of transaction i am dealing with and based on that i would know which table to link further. Now how can i achieve this in Entity Frame work. This is the most important step. I have done this many times in my other languages but now using EF i am stuck. Please help. I have checked a lot online but i have not found it. I am new to MVC and entity frame work architecture. Any guidance would be highly appreciated. Ranjit

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  • Do I have to implement Add/Delete methods in my NHibernate entities ?

    - by Lisa
    This is a sample from the Fluent NHibernate website: Compared to the Entitiy Framework I have ADD methods in my POCO in this code sample using NHibernate. With the EF I did context.Add or context.AddObject etc... the context had the methods to put one entity into the others entity collection! Do I really have to implement Add/Delete/Update methods (I do not mean the real database CRUD operations!) in a NHibernate entity ? public class Store { public virtual int Id { get; private set; } public virtual string Name { get; set; } public virtual IList<Product> Products { get; set; } public virtual IList<Employee> Staff { get; set; } public Store() { Products = new List<Product>(); Staff = new List<Employee>(); } public virtual void AddProduct(Product product) { product.StoresStockedIn.Add(this); Products.Add(product); } public virtual void AddEmployee(Employee employee) { employee.Store = this; Staff.Add(employee); } }

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  • How to use different providers for Linq to entities?

    - by Anders Svensson
    I'm trying to familiarize myself a bit more with database programming, and I'm looking at different ways of creating a data access layer for applications. I've tried out a few ways but there is such a jungle of different database technologies that I don't know what to learn. For instance I've tried using datasets with tableadapters. Using that I am able to switch data provider rather easily (by programming against the interfaces such as IDbConnection). This is one thing I would want to achieve. But I also know everyone's talking about LINQ, and I'm trying to get to know that a bit better too. So I have tried using Linq to Sql classes as the data access layer as well, but apparently this is not provider independent (works only for SQL Server). So then I read about the Entity Framework (which just as Linq to SQL apparently has gotten its share of bashing already...). It's supposed to be provider independent everybody says, but how? I tried out a tutorial to create an entity data model, but the only providers to choose from were SQL Server/Express. Just for learning purposes, I would like to know how to use the entity framework with MS Access/OleDb. Also, I would appreciate some input on what is the preferred database technology for data access. Is it LINQ still after all the bashing, or should you just use datasets because they are provider independent? Any pointers for what to learn would be great, because it's just too much to learn it all if I'm not going to use it in the end...!

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  • Cannot truncate table because it is being referenced by a FOREIGN KEY constraint?

    - by ctrlShiftBryan
    Using MSSQL2005, Can I truncate a table with a foreign key constraint if I first truncate the child table(the table with the primary key of the FK relationship)? I know I can use a DELETE without a where clause and then RESEED the identity OR Remove the FK, truncate and recreate but I thought as long as you truncate the child table you'll be OK however I'm getting a "Cannot truncate table 'TableName' because it is being referenced by a FOREIGN KEY constraint." error.

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  • What is the best schema design for child collection with a "primary" entity

    - by erg39
    Here is the scenario: You have a Persons table with a one-to-many relationship with an Addresses table, where one of the Address rows is the "primary" Address. Is it better in a normalized schema to Use a Persons.PrimaryAddressID to access the "primary" Address for a Person or Use an Addresses.IsPrimary bit column to reference the "primary" Address for a Person via Addresses.PersonID or Other and why?

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  • ObjectContext.SaveChanges() fails with SQL CE

    - by David Veeneman
    I am creating a model-first Entity Framework 4 app that uses SQL CE as its data store. All is well until I call ObjectContext.SaveChanges() to save changes to the entities in the model. At that point, SaveChanges() throws a System.Data.UpdateException, with an inner exception message that reads as follows: Server-generated keys and server-generated values are not supported by SQL Server Compact. I am completely puzzled by this message. Any idea what is going on and how to fix it? Thanks. Here is the Exception dump: System.Data.UpdateException was unhandled Message=An error occurred while updating the entries. See the inner exception for details. Source=System.Data.Entity StackTrace: at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter) at System.Data.EntityClient.EntityAdapter.Update(IEntityStateManager entityCache) at System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options) at System.Data.Objects.ObjectContext.SaveChanges() at FsDocumentationBuilder.ViewModel.Commands.SaveFileCommand.Execute(Object parameter) in D:\Users\dcveeneman\Documents\Visual Studio 2010\Projects\FsDocumentationBuilder\FsDocumentationBuilder\ViewModel\Commands\SaveFileCommand.cs:line 68 at MS.Internal.Commands.CommandHelpers.CriticalExecuteCommandSource(ICommandSource commandSource, Boolean userInitiated) at System.Windows.Controls.Primitives.ButtonBase.OnClick() at System.Windows.Controls.Button.OnClick() at System.Windows.Controls.Primitives.ButtonBase.OnMouseLeftButtonUp(MouseButtonEventArgs e) at System.Windows.UIElement.OnMouseLeftButtonUpThunk(Object sender, MouseButtonEventArgs e) at System.Windows.Input.MouseButtonEventArgs.InvokeEventHandler(Delegate genericHandler, Object genericTarget) at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target) at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs) at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised) at System.Windows.UIElement.ReRaiseEventAs(DependencyObject sender, RoutedEventArgs args, RoutedEvent newEvent) at System.Windows.UIElement.OnMouseUpThunk(Object sender, MouseButtonEventArgs e) at System.Windows.Input.MouseButtonEventArgs.InvokeEventHandler(Delegate genericHandler, Object genericTarget) at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target) at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs) at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised) at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args) at System.Windows.UIElement.RaiseTrustedEvent(RoutedEventArgs args) at System.Windows.UIElement.RaiseEvent(RoutedEventArgs args, Boolean trusted) at System.Windows.Input.InputManager.ProcessStagingArea() at System.Windows.Input.InputManager.ProcessInput(InputEventArgs input) at System.Windows.Input.InputProviderSite.ReportInput(InputReport inputReport) at System.Windows.Interop.HwndMouseInputProvider.ReportInput(IntPtr hwnd, InputMode mode, Int32 timestamp, RawMouseActions actions, Int32 x, Int32 y, Int32 wheel) at System.Windows.Interop.HwndMouseInputProvider.FilterMessage(IntPtr hwnd, WindowMessage msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at System.Windows.Interop.HwndSource.InputFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled) at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o) at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs) at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler) at System.Windows.Threading.Dispatcher.InvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs) at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam) at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg) at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame) at System.Windows.Threading.Dispatcher.PushFrame(DispatcherFrame frame) at System.Windows.Threading.Dispatcher.Run() at System.Windows.Application.RunDispatcher(Object ignore) at System.Windows.Application.RunInternal(Window window) at System.Windows.Application.Run(Window window) at System.Windows.Application.Run() at FsDocumentationBuilder.App.Main() in D:\Users\dcveeneman\Documents\Visual Studio 2010\Projects\FsDocumentationBuilder\FsDocumentationBuilder\obj\x86\Debug\App.g.cs:line 50 at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args) at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args) at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly() at System.Threading.ThreadHelper.ThreadStart_Context(Object state) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state) at System.Threading.ThreadHelper.ThreadStart() InnerException: System.Data.EntityCommandCompilationException Message=An error occurred while preparing the command definition. See the inner exception for details. Source=System.Data.Entity StackTrace: at System.Data.Mapping.Update.Internal.UpdateTranslator.CreateCommand(DbModificationCommandTree commandTree) at System.Data.Mapping.Update.Internal.DynamicUpdateCommand.CreateCommand(UpdateTranslator translator, Dictionary`2 identifierValues) at System.Data.Mapping.Update.Internal.DynamicUpdateCommand.Execute(UpdateTranslator translator, EntityConnection connection, Dictionary`2 identifierValues, List`1 generatedValues) at System.Data.Mapping.Update.Internal.UpdateTranslator.Update(IEntityStateManager stateManager, IEntityAdapter adapter) InnerException: System.NotSupportedException Message=Server-generated keys and server-generated values are not supported by SQL Server Compact. Source=System.Data.SqlServerCe.Entity StackTrace: at System.Data.SqlServerCe.SqlGen.DmlSqlGenerator.GenerateReturningSql(StringBuilder commandText, DbModificationCommandTree tree, ExpressionTranslator translator, DbExpression returning) at System.Data.SqlServerCe.SqlGen.DmlSqlGenerator.GenerateInsertSql(DbInsertCommandTree tree, List`1& parameters, Boolean isLocalProvider) at System.Data.SqlServerCe.SqlGen.SqlGenerator.GenerateSql(DbCommandTree tree, List`1& parameters, CommandType& commandType, Boolean isLocalProvider) at System.Data.SqlServerCe.SqlCeProviderServices.CreateCommand(DbProviderManifest providerManifest, DbCommandTree commandTree) at System.Data.SqlServerCe.SqlCeProviderServices.CreateDbCommandDefinition(DbProviderManifest providerManifest, DbCommandTree commandTree) at System.Data.Common.DbProviderServices.CreateCommandDefinition(DbCommandTree commandTree) at System.Data.Common.DbProviderServices.CreateCommand(DbCommandTree commandTree) at System.Data.Mapping.Update.Internal.UpdateTranslator.CreateCommand(DbModificationCommandTree commandTree) InnerException:

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  • error 2016: Condition cannot be specified for Column member

    - by IP
    I am having some issues with Entity Framework in VS2010 The problem I'm getting is described very well here... http://social.msdn.microsoft.com/Forums/en/adonetefx/thread/cacf6a76-09a8-4c90-9502-d8b87c2f6bea It's basically happening when a Foreign key is pointed at the primary key of another table...but if I take off the StoreGeneratedPattern as "Identity", then it tries to insert a value into the identity field ** EDIT So, what it seems to be is that EF4 can't handle a null relationship when the primary key is set to StoreGeneratedPattern="Identity". If I create a FK pointing to this primary key, and make it nullable (effectively creating a 0...M relationship), then it throws this compilation error. Removing StoreGeneratedPattern="Identity" fixes the issue, but causes issues elseware It works if the foreign key is set to not nullable

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  • How to perform a many-to-many Linq query with Include in the EF.

    - by despart
    Hi, I don't know how to perform this query using Linq and the EF. Imagine I have three tables A, B and C. A and B have a many-to-many relationship. B and C have a 1-to-many relationship. I want to obtain records from B including C but filtering from A's Id. I can get easily the records from B: var b = Context.A.Where(x => x.Id.Equals(aId)).SelectMany(x => x.B); but when I try to include C I don't know how to do it: //This doesn't work var b = Context.A.Where(x => x.Id.Equals(aId)).SelectMany(x => x.B.Include("C")); Also I've tried this with no luck (it is equivalent to the above): //Not working var b = (from a in Context.A.Where(x => x.Id.Equals(aId)) from b in a.B.Include("C") select b); Thanks for your help.

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  • Eager loading in EF1.0

    - by Dave Swersky
    I have a many-to-many relationship: Application - Applications_Servers - Server This is set up in my Entity Data Model and all is well. My problem is that I'd like to eager-load the whole graph of Applications so that I have an IEnumerable<Applications>, each Application member populated with the Servers collection associated by the many-to-many relationship. Normally this wouldn't be a problem, but according to my research there must be a navigation property between Application and Server. This is not the case for me because my Applications_Servers join table has more in it than just the two keys. Therefore, there is no navigation property directly between Application and Server, and this doesn't work: var apps = (from a in context.Application.Include("Server") select a).ToList(); I get an error saying there is no navigation property on Application called "Server", and that's correct, there is none. How do I write the query to eager-load my Applications with their Servers in this case?

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  • Can the following Domain Entity contain logic for creating/deleting other entities?

    - by user702769
    a) As far as I understand it, in most cases Domain Model DM doesn't contain code for creating/deleting domain entities, but instead it is the job of layers ( ie service layer or UI layer ) on top of DM to create/delete domain entities? b) Domain entities are modelled after real world entities. Assuming particular real world entity being abstracted does have the functionality of creating/deleting other real world entities, then I assume the domain entity abstracting this real world entity could also contain logic for creating/deleting other entities? class RobotDestroyerCreator { ... void heavyThinking() { ... if(...) unitOfWork.registerDelete(robot); ... if(...) { var robotNew = new Robot(...); unitOfWork.registerNew(robotNew); { ... } } Thank you

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  • Visual Studio 2010 RC and Entity Framework 4 RC Support in the New Version of ADO.NET Data Providers

    Devart has recently announced the release of dotConnect products for Oracle, MySQL, PostgreSQL, and SQLite - ADO.NET providers that offer Entity Framework support, LINQ to SQL support, and contain an ORM model designer for developing LINQ to SQL and EF models based on different database engines. New dotConnect ADO.NET providers offer complete support for Visual Studio 2010 Release Candidate and Entity Framework 4 Release Candidate. Entity Developer 2.80, a designer for modeling and code generation...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • « Entity Framework : structurez et optimisez votre couche d'accès aux données », invitation à la conférence gratuite de Microsoft du 18 mars

    Entity Framework : structurez et optimisez votre couche d'accès aux données Assistez gratuitement aux après-midi du développement de Microsoft Les après-midi du développement sont des conférences gratuites organisées par Microsoft qui permettent aux développeurs de découvrir de nouvelles problématiques. L'occasion de monter en compétence et d'échanger avec des experts sur un sujet précis. La première conférence de 2011 se tiendra le 18 mars entre 14h et 18h sur le campus de Microsoft France. Elle permettra de découvrir la technologie d'accès aux données introduite par le Framework .NET 3.5 SP1 : Entity Framework. Au cours de cette session, l'utilisation d'Entity Framework dans les scénar...

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  • Reference to undeclared entity 'nbsp' - why?

    - by Charles
    I have the following line of code: XDocument formConfiguration = XDocument.Load(ConfigurationManager.AppSettings["XMLFileURL"]); I get the following exception message: Reference to undeclared entity 'nbsp' There are no   sequences in the XML. There are no "&" characters in the XML. Where could this be coming from? Thanks, Charles

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  • Cannot remove an entity that has not been attached on delete

    - by mazhar
    public IQueryable<Feature> GetAllFeaturesByLinkAndParentID(int id) { return from gp in db.Features where gp.int_ParentId == id && gp.bit_IsLink == false select gp; } var DeleteFeature = FeatureRepository.GetAllFeaturesByLinkAndParentID(GetFeatureId); _db.Features.DeleteAllOnSubmit(DeleteFeature); _db.SubmitChanges(); how will i remove the error Cannot remove an entity that has not been attached in this code

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  • Cannot attach an entity that already exists.

    - by coure06
    i am trying to update code via Linq, but getting this error Cannot attach an entity that already exists. C# code is here var con = (from c in cmsContentTable where c.ContentName == contentId select c).FirstOrDefault(); cmsContentTable.Attach(con); con.ContentData = "New Value"; cmsContentTable.Context.SubmitChanges();

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  • entity set expansion python

    - by Nicolas M.
    Do you know of any existing implementation in any language (preferably python) of any entity set expansion algorithms, such that the one from Google sets ? ( http://labs.google.com/sets ) I couldn't find any library implementing such algorithms and I'd like to play with some of those to see how they would perform on some specific task I would like to implement. Any help is welcome ! Thanks a lot for your help, Regards, Nicolas.

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  • Unity framework - creating & disposing Entity Framework datacontexts at the appropriate time

    - by TobyEvans
    Hi there, With some kindly help from StackOverflow, I've got Unity Framework to create my chained dependencies, including an Entity Framework datacontext object: using (IUnityContainer container = new UnityContainer()) { container.RegisterType<IMeterView, Meter>(); container.RegisterType<IUnitOfWork, CommunergySQLiteEntities>(new ContainerControlledLifetimeManager()); container.RegisterType<IRepositoryFactory, SQLiteRepositoryFactory>(); container.RegisterType<IRepositoryFactory, WCFRepositoryFactory>("Uploader"); container.Configure<InjectedMembers>() .ConfigureInjectionFor<CommunergySQLiteEntities>( new InjectionConstructor(connectionString)); MeterPresenter meterPresenter = container.Resolve<MeterPresenter>(); this works really well in creating my Presenter object and displaying the related view, I'm really pleased. However, the problem I'm running into now is over the timing of the creation and disposal of the Entity Framework object (and I suspect this will go for any IDisposable object). Using Unity like this, the SQL EF object "CommunergySQLiteEntities" is created straight away, as I've added it to the constructor of the MeterPresenter public MeterPresenter(IMeterView view, IUnitOfWork unitOfWork, IRepositoryFactory cacheRepository) { this.mView = view; this.unitOfWork = unitOfWork; this.cacheRepository = cacheRepository; this.Initialize(); } I felt a bit uneasy about this at the time, as I don't want to be holding open a database connection, but I couldn't see any other way using the Unity dependency injection. Sure enough, when I actually try to use the datacontext, I get this error: ((System.Data.Objects.ObjectContext)(unitOfWork)).Connection '((System.Data.Objects.ObjectContext)(unitOfWork)).Connection' threw an exception of type 'System.ObjectDisposedException' System.Data.Common.DbConnection {System.ObjectDisposedException} My understanding of the principle of IoC is that you set up all your dependencies at the top, resolve your object and away you go. However, in this case, some of the child objects, eg the datacontext, don't need to be initialised at the time the parent Presenter object is created (as you would by passing them in the constructor), but the Presenter does need to know about what type to use for IUnitOfWork when it wants to talk to the database. Ideally, I want something like this inside my resolved Presenter: using(IUnitOfWork unitOfWork = new NewInstanceInjectedUnitOfWorkType()) { //do unitOfWork stuff } so the Presenter knows what IUnitOfWork implementation to use to create and dispose of straight away, preferably from the original RegisterType call. Do I have to put another Unity container inside my Presenter, at the risk of creating a new dependency? This is probably really obvious to a IoC guru, but I'd really appreciate a pointer in the right direction thanks Toby

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  • ADO.net entity framework- Bridge entities

    - by user308806
    Hello, I have used ADO.net entity framwork to build my application. My application's data diagram contains 2 bridge entities. The problem is that I can not see or access these bridge entities in ADO.net framework using domain services. Do you have any idea how to use CRUD operations on them? Regards,

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