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  • How do I generate Entity Framework 4.0 classes from the command line that have different names than

    - by Josh Kodroff
    I want to generate Entity Framework 4.0 classes from a (legacy) database from a command line, but I have 2 transformations I want: Tables/columns are lowerCamelCase and I want my classes/members to be UpperCamelCase. I want to suffix my classes with "Dto". Any idea how this might be accomplished? I'm a total newbie to EF, but I have a decent understanding of Linq to Sql and was able to accomplish the same task by doing: sqlmetal - dbml - xml mapping file and .cs file.

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  • Efficient mapping of game entity positions in Java

    - by byte
    In Java (Swing), say I've got a 2D game where I have various types of entities on the screen, such as a player, bad guys, powerups, etc. When the player moves across the screen, in order to do efficient checking of what is in the immediate vicinity of the player, I would think I'd want indexed access to the things that are near the character based on their position. For example, if player 'P' steps onto element 'E' in the following example... | | | | | | | | | |P| | | | |E| | | | | | | | | ... would be to do something like: if(player.getPosition().x == entity.getPosition().x && entity.getPosition.y == thing.getPosition().y) { //do something } And thats fine, but that implies that the entities hold their positions, and therefor if I had MANY entities on the screen I would have to loop through all possible entities available and check each ones position against the player position. This seems really inefficient especially if you start getting tons of entities. So, I would suspect I'd want some sort of map like Map<Point, Entity> map = new HashMap<Point, Entity>(); And store my point information there, so that I could access these entities in constant time. The only problem with that approach is that, if I want to move an entity to a different point on the screen, I'd have to search through the values of the HashMap for the entity I want to move (inefficient since I dont know its Point position ahead of time), and then once I've found it remove it from the HashMap, and re-insert it with the new position information. Any suggestions or advice on what sort of data structure / storage format I ought to be using here in order to have efficient access to Entities based on their position, as well as Position's based on the Entity?

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  • MVVM: where is the best place to integrate an id counter, in ViewModel or Repository or... ?

    - by msfanboy
    Hello, I am using http://loungerepo.codeplex.com/ this library needs a unique id when I persist my entities to the repository. I decided for integer not Guid. The question is now where do I retrieve a new integer and how do I do it? This is my current approach in the SchoolclassAdministrationViewModel.cs: public SchoolclassAdministrationViewModel() { _schoolclassRepo = new SchoolclassRepository(); _pupilRepo = new PupilRepository(); _subjectRepo = new SubjectRepository(); _currentSchoolclass = new SchoolclassModel(); _currentPupil = new PupilModel(); _currentSubject = new SubjectModel(); ... } private void AddSchoolclass() { // get the last free id for a schoolclass entity _currentSchoolclass.SchoolclassID = _schoolclassRepo.LastID; // add the new schoolclass entity to the repository _schoolclassRepo.Add(SchoolclassModel.SchoolclassModelToSchoolclass(_currentSchoolclass)); // add the new schoolclass entity to the ObservableCollection bound to the View Schoolclasses.Add(_currentSchoolclass); // Create a new schoolclass entity and the bound UI controls content gets cleaned CurrentSchoolclass = new SchoolclassModel(); } public class SchoolclassRepository : IRepository<Schoolclass> { private int _lastID; public SchoolclassRepository() { _lastID = FetchLastId(); } public void Add(Schoolclass entity) { //repo.Store(entity); } private int FetchLastId() { return // repo.GetIDOfLastEntryAndDoInc++ } public int LastID { get { return _lastID; } } } Explanation: Every time the user switches to the SchoolclassAdministrationViewModel which is datatemplated with a UserControl the saVM Ctor is called and the schoolclass repository is created wherein the FetchLastId() is called and I am up to date with the last ID doing a inc++ on it to get the free one... Do you have any better ideas? What I do not like about my current apporach: -Having a private method in repositry class because a repositry is to fetch data only not "entity logic" like the counter - Having to access from the ViewModel a public property - located in the repository -, actually its not the ViewModel concern to get a entity id and assign it. Actually the ViewModel should ask for a schoolclass POCO and get a SchoolclassModel to bind to the UI. But then I have again to re-read the Schoolclass properties into the SchoolclassModel properties what I want to avoid.

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  • Multiple "ObjectChangeTracker" getting created, can it be avoided?

    - by user555937
    Hi, We are working on a POC where we have following architecture (MVVM), WPF(Client) + WCF + Model(DataAccess)+ ADO.Net Entity Framework 4.0 (with SQL Server 2008 R2 as DB) All are different projects. In the DataAccess layer we have created different Entity Models(edmx) based on the functionality. The tables under perticular flow are grouped and created different entity models. We are using self tracking entities to and fro to communicate with the WPF client through wcf service. For Single model everything works fine. But when we created a Multiple models then few issues started coming. Mutliple models have few duplicate tables/entities. Two probels are, 1) When we try to access entities from different models mutiple objects "ObjectChangeTracker" are getting created. E.g. CompanyModel(edmx) - Company(Entity) - ObjectChangeTracker, ObjectState ProductModel(edmx) - Customer(Entity) - ObjectChangeTracker1, ObjectState1 OrderModel(edmx) - Oder(Entity) - ObjectChangeTracker2, ObjectState2 Is there any way to avoid this? 2) There are few tables which shared across the Models, E.g. Company(Entity) is used in All above mdoels. During compile time it does not thow any error. But run time It gives error saying "Schema specified is not valid. Errors: The mapping of CLR type to EDM type is ambiguous because multiple CLR types match the EDM type "Company"".. To resolve this, we renamed the entities with some prefix to make them Unique. Is there any other way we can resolve this without changing the name of the entity in the same assembly? Thanks in advance and appreciate if anyone has approach for these issues. Thanks, Kiran

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  • Nested Entities and calculation on leaf entity property - SQL or NoSQL approach

    - by Chandu
    I am working on a hobby project called Menu/Recipe Management. This is how my entities and their relations look like. A Nutrient has properties Code and Value An Ingredient has a collection of Nutrients A Recipe has a Collection of Ingredients and occasionally can have a collection of other recipes A Meal has a Collection of Recipes and Ingredients A Menu has a Collection of Meals The relations can be depicted as In one of the pages, for a selected menu I need to display the effective nutrients information calculated based on its constituents (Meals, Recipes, Ingredients and the corresponding nutrients). As of now am using SQL Server to store the data and I am navigating the chain from my C# code, starting from each meal of the menu and then aggregating the nutrient values. I think this is not an efficient way as this calculation is being done every time the page is requested and the constituents change occasionally. I was thinking about a having a background service that maintains a table called MenuNutrients ({MenuId, NutrientId, Value}) and will populate/update this table with the effective nutrients when any of the component (Meal, Recipe, Ingredient) changes. I feel that a GraphDB would be a good fit for this requirement, but my exposure to NoSQL is limited. I want to know what are the alternative solutions/approaches to this requirement of displaying the nutrients of a given menu. Hope my description of the scenario is clear.

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  • Sys.WebForms.PageRequestManagerServerErrorException: An entity object cannot be referenced by multiple instances of IEntityChangeTracker [closed]

    - by Mingebag
    `Story: I have a strange error when I try to save something I got this error message An entity object cannot be referenced by multiple instances of IEntityChangeTracker. I really don’t know what that is and why is it appear, it appears only when I try to save something my insert and update is working, only when I try to save something in db from my Telerik grid if (this.annualVacationList != null) { List<AnnualVacation> vacationToSave = this.annualVacationList; IEnumerable<AnnualVacation> existing = paramUser.AnnualVacations; foreach (AnnualVacation toSave in vacationToSave) { AnnualVacation existingItem = existing.Where(x => x.AnnualVacationId == toSave.AnnualVacationId).SingleOrDefault(); if (existingItem == null) { ctx.AddToAnnualVacations(toSave); } else { existingItem.FromDate = toSave.FromDate; existingItem.ToDate = toSave.ToDate; existingItem.WorkingTime = toSave.WorkingTime; existingItem.VacationDays = toSave.VacationDays; } } } ctx.SaveChanges(); } After debugging I have seen that the code brake down in the Project.Name.Designer.cs ..... O.o public void AddToAnnualVacations(AnnualVacation annualVacation) { base.AddObject("AnnualVacations", annualVacation); }

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  • Where should I start with debugging my exchange server?

    - by joadha
    I'm (foolishly?) attempting to install Exchange on top of Windows Server 2008 (64-bit) over Virtual Box running on Mac OSX Lion. Everything went smoothly until I got to the "Readiness Checks" tab. Readiness failed spectacularly on Hub Transport Role and Mailbox Role prereqs. Before I go too far down the rabbit hole in attempting to remedy this, I was hoping I could get some input on where to start in all of this. I already set up the following Active Directory roles, but it didn't seem to help: Active Directory Domain Services Active Directory Lightweight Directory Services I also enabled an Application Server role. Those three are the only roles I've set up-- I cannot locate within Server Manager the Organization Manager role or any of the other roles referenced in the list of borkedness below. Is this a typical experience in Exchange installation? Is there a tutorial created by somebody outside of Microsoft? Here's the output from Readiness Checks: Summary: 5 item(s). 2 succeeded, 3 failed. Elapsed time: 00:00:53 Configuring Prerequisites Completed Elapsed Time: 00:00:00 Languages Prerequisites Completed Elapsed Time: 00:00:09 Hub Transport Role Prerequisites Failed Error: Active Directory does not exist or cannot be contacted. Click here for help... http://go.microsoft.com/fwlink/? linkid=30939&l=en&v=ExBPA.14&id=51e5500d-8b18-4eee-bb8e-925d063b60a1 Error: You must be a member of the 'Organization Management' role group or 'Enterprise Admins' group to continue. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=1d750594-9222-44d7-8f80-45e522e889e6 Error: Setup encountered a problem while validating the state of Active Directory: Could not find information about the local domain. Click here for help... http://technet.microsoft.com/en-US/library/ms.exch.err.default(EXCHG.141).aspx?v=14.1.218.11&e=ms.exch.err.Ex28883C&l=0&cl=cp Error: You must be logged on as an Exchange organization administrator to install or upgrade the first Hub Transport server role in the topology. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=e58f51fd-2c66-4a4b-914a-628dccf9a09f Error: The 'IIS 6 Metabase Compatibility' component is not installed. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=0a71c4f6-68de-40f7-94cf-74b73cbda37b Error: The 'IIS 7 Basic Authentication' component required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error: The 'IIS 7 Windows Authentication' component is required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error: The 'IIS 7 .NET Extensibility' component is required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=5f29a861-f472-4f11-a23a-04155373f5ed Error: This computer is not part of a Windows domain. Click here for help... http://technet.microsoft.com/en-US/library/ms.exch.err.default(EXCHG.141).aspx?v=14.1.218.11&e=ms.exch.err.Ex28883C&l=0&cl=cp Error: The user is not logged on to a Windows domain Click here for help... http://technet.microsoft.com/en-US/library/ms.exch.err.default(EXCHG.141).aspx?v=14.1.218.11&e=ms.exch.err.Ex28883C&l=0&cl=cp Warning: This computer requires the Microsoft Office 2010 Filter Packs. Please install the software from http://go.microsoft.com/fwlink/?LinkID=191548 Warning: The 'IIS 6 Management Console' component is recommended as it allows for the administration of all server roles. Install the component via Server Manager. Warning: Setup cannot verify that the 'Host' (A) record for this computer exists within the DNS database on server 10.1.10.1. Elapsed Time: 00:00:15 Client Access Role Prerequisites Failed Error: Active Directory does not exist or cannot be contacted. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=51e5500d-8b18-4eee-bb8e-925d063b60a1 Error: Unable to read data from the Metabase. Ensure that Microsoft Internet Information Services is installed. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=a4a4d339-4009-4fb7-b842-ca2ba79f13f0 Error: The World Wide Web (W3SVC) service is either disabled or not installed on this computer. You must exit Setup, install the required component, then restart the Setup process. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=9eeaa77f-4d46-4d9a-9c36-f262a075392b Error: You must be a member of the 'Organization Management' role group or 'Enterprise Admins' group to continue. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=1d750594-9222-44d7-8f80-45e522e889e6 Error: Setup encountered a problem while validating the state of Active Directory: Could not find information about the local domain. Click here for help... http://technet.microsoft.com/en-US/library/ms.exch.err.default(EXCHG.141).aspx?v=14.1.218.11&e=ms.exch.err.Ex28883C&l=0&cl=cp Error: You must be logged on as an Exchange organization administrator to install or upgrade the first Client Access server role in the topology. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=e58f51fd-2c66-4a4b-914a-628dccf9a09f Error: The 'IIS 6 Metabase Compatibility' component is not installed. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=0a71c4f6-68de-40f7-94cf-74b73cbda37b Error: The 'IIS 6 Management Console' component is not installed. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=0a71c4f6-68de-40f7-94cf-74b73cbda37b Error: The 'IIS 7 Dynamic Content Compression' component is required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/? linkid=30939&l=en&v=ExBPA.14&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error: The 'IIS 7 Static Content Compression' component is required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error: The 'IIS 7 Basic Authentication' component required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error: The 'IIS 7 Windows Authentication' component is required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error: The 'IIS 7 Digest Authentication' component is required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error: The 'IIS 7 .NET Extensibility' component is required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=5f29a861-f472-4f11-a23a-04155373f5ed Error: This computer is not part of a Windows domain. Click here for help... http://technet.microsoft.com/en-US/library/ms.exch.err.default(EXCHG.141).aspx?v=14.1.218.11&e=ms.exch.err.Ex28883C&l=0&cl=cp Error: The user is not logged on to a Windows domain Click here for help... http://technet.microsoft.com/en-US/library/ms.exch.err.default(EXCHG.141).aspx?v=14.1.218.11&e=ms.exch.err.Ex28883C&l=0&cl=cp Warning: Setup cannot verify that the 'Host' (A) record for this computer exists within the DNS database on server 10.1.10.1. Elapsed Time: 00:00:14 Mailbox Role Prerequisites Failed Error: Active Directory does not exist or cannot be contacted. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=51e5500d-8b18-4eee-bb8e-925d063b60a1 Error: Unable to read data from the Metabase. Ensure that Microsoft Internet Information Services is installed. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=a4a4d339-4009-4fb7-b842-ca2ba79f13f0 Error: The World Wide Web (W3SVC) service is either disabled or not installed on this computer. You must exit Setup, install the required component, then restart the Setup process. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=9eeaa77f-4d46-4d9a-9c36-f262a075392b Error: You must be a member of the 'Organization Management' role group or 'Enterprise Admins' group to continue. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=1d750594-9222-44d7-8f80-45e522e889e6 Error: Setup encountered a problem while validating the state of Active Directory: Could not find information about the local domain. Click here for help... http://technet.microsoft.com/en-US/library/ms.exch.err.default(EXCHG.141).aspx?v=14.1.218.11&e=ms.exch.err.Ex28883C&l=0&cl=cp Error: You must be logged on as an Exchange organization administrator to install or upgrade the first Mailbox server role in the topology. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=e58f51fd-2c66-4a4b-914a-628dccf9a09f Error: The 'IIS 6 Metabase Compatibility' component is not installed. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=0a71c4f6-68de-40f7-94cf-74b73cbda37b Error: The 'IIS 6 Management Console' component is not installed. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=0a71c4f6-68de-40f7-94cf-74b73cbda37b Error: The 'IIS 7 Basic Authentication' component required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error: The 'IIS 7 Windows Authentication' component is required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=41a25c5e-0d39-4e55-a1f0-7be885982236 Error: The 'IIS 7 .NET Extensibility' component is required. Install the component via Server Manager. Click here for help... http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.14&id=5f29a861-f472-4f11-a23a-04155373f5ed Error: This computer is not part of a Windows domain. Click here for help... http://technet.microsoft.com/en-US/library/ms.exch.err.default(EXCHG.141).aspx?v=14.1.218.11&e=ms.exch.err.Ex28883C&l=0&cl=cp Error: The user is not logged on to a Windows domain Click here for help... http://technet.microsoft.com/en-US/library/ms.exch.err.default(EXCHG.141).aspx?v=14.1.218.11&e=ms.exch.err.Ex28883C&l=0&cl=cp Warning: This computer requires the Microsoft Office 2010 Filter Packs. Please install the software from http://go.microsoft.com/fwlink/?LinkID=191548 Warning: Setup cannot verify that the 'Host' (A) record for this computer exists within the DNS database on server 10.1.10.1. Elapsed Time: 00:00:14

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  • The Interaction between Three-Tier Client/Server Model and Three-Tier Application Architecture Model

    The three-tier client/server model is a network architectural approach currently used in modern networking. This approach divides a network in to three distinct components. Three-Tier Client/Server Model Components Client Component Server Component Database Component The Client Component of the network typically represents any device on the network. A basic example of this would be computer or another network/web enabled devices that are connected to a network. Network clients request resources on the network, and are usually equipped with a user interface for the presentation of the data returned from the Server Component. This process is done through the use of various software clients, and example of this can be seen through the use of a web browser client. The web browser request information from the Server Component located on the network and then renders the results for the user to process. The Server Components of the network return data based on specific client request back to the requesting client.  Server Components also inherit the attributes of a Client Component in that they are a device on the network and that they can also request information from other Server Components. However what differentiates a Client Component from a Server Component is that a Server Component response to requests from devices on the network. An example of a Server Component can be seen in a web server. A web server listens for new requests and then interprets the request, processes the web pages, and then returns the processed data back to the web browser client so that it may render the data for the user to interpret. The Database Component of the network returns unprocessed data from databases or other resources. This component also inherits attributes from the Server Component in that it is a device on a network, it can request information from other server components and database components, and it also listens for new requests so that it can return data when needed. The three-tier client/server model is very similar to the three-tier application architecture model, and in fact the layers can be mapped to one another. Three-Tier Application Architecture Model Presentation Layer/Logic Business Layer/Logic Data Layer/Logic The Presentation Layer including its underlying logic is very similar to the Client Component of the three-tiered model. The Presentation Layer focuses on interpreting the data returned by the Business Layer as well as presents the data back to the user.  Both the Presentation Layer and the Client Component focus primarily on the user and their experience. This allows for segments of the Business Layer to be distributable and interchangeable because the Presentation Layer is not directly integrated in with Business Layer. The Presentation Layer does not care where the data comes from as long as it is in the proper format. This allows for the Presentation Layer and Business Layer to be stored on one or more different servers so that it can provide a higher availability to clients requesting data. A good example of this is a web site that uses load balancing. When a web site decides to take on the task of load balancing they must obtain a network device that sits in front of a one or machines in order to distribute the request across multiple servers. When a user comes in through the load balanced device they are redirected to a specific server based on a few factors. Common Load Balancing Factors Current Server Availability Current Server Response Time Current Server Priority The Business Layer and corresponding logic are business rules applied to data prior to it being sent to the Presentation Layer. These rules are used to manipulate the data coming from the Data Access Layer, in addition to validating any data prior to being stored in the Data Access Layer. A good example of this would be when a user is trying to create multiple accounts under one email address. The Business Layer logic can prevent duplicate accounts by enforcing a unique email for every new account before the data is even stored in the Data Access Layer. The Server Component can be directly tied to this layer in that the server typically stores and process the Business Layer before it is returned to the end-user via the Presentation Layer. In addition the Server Component can also run automated process through the Business Layer on the data in the Data Access Layer so that additional business analysis can be derived from the data that has been already collected. The Data Layer and its logic are responsible for storing information so that it can be easily retrieved. Typical in most modern applications data is stored in a database management system however data can also be in the form of files stored on a file server. In addition a database can take on one of several forms. Common Database Formats XML File Pipe Delimited File Tab Delimited File Comma Delimited File (CSV) Plain Text File Microsoft Access Microsoft SQL Server MySql Oracle Sybase The Database component of the Networking model can be directly tied to the Data Layer because this is where the Data Layer obtains the data to return back the Business Layer. The Database Component basically allows for a place on the network to store data for future use. This enables applications to save data when they can and then quickly recall the saved data as needed so that the application does not have to worry about storing the data in memory. This prevents overhead that could be created when an application must retain all data in memory. As you can see the Three-Tier Client/Server Networking Model and the Three-Tiered Application Architecture Model rely very heavily on one another to function especially if different aspects of an application are distributed across an entire network. The use of various servers and database servers are wonderful when an application has a need to distribute work across the network. Network Components and Application Layers Interaction Database components will store all data needed for the Data Access Layer to manipulate and return to the Business Layer Server Component executes the Business Layer that manipulates data so that it can be returned to the Presentation Layer Client Component hosts the Presentation Layer that  interprets the data and present it to the user

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  • Getting Error whileInitializing entities [closed]

    - by R76
    I am new'b as WPF Dev. I am developing Window application in WPF using mvvmlight framework. I have created database in Sqlserver compact 4.0. I have made a Ado.net Entity Data Model. When I trying to initialize the Entity object in service it throws the error like: Error 'The invocation of the constructor on type 'PointOfSale.ViewModels.ProductsViewModel' that matches the specified binding constraints threw an exception.' Line number '7' and line position '10'. stack Trace at System.Windows.Markup.XamlReader.RewrapException(Exception e, IXamlLineInfo lineInfo, Uri baseUri) at System.Windows.Markup.WpfXamlLoader.Load(XamlReader xamlReader, IXamlObjectWriterFactory writerFactory, Boolean skipJournaledProperties, Object rootObject, XamlObjectWriterSettings settings, Uri baseUri) at System.Windows.Markup.WpfXamlLoader.LoadBaml(XamlReader xamlReader, Boolean skipJournaledProperties, Object rootObject, XamlAccessLevel accessLevel, Uri baseUri) at System.Windows.Markup.XamlReader.LoadBaml(Stream stream, ParserContext parserContext, Object parent, Boolean closeStream) at System.Windows.Application.LoadComponent(Object component, Uri resourceLocator) at PointOfSale.MainWindow.InitializeComponent() in e:\VarniApplication\PointOfSale\PointOfSale\MainWindow.xaml:line 1 at PointOfSale.MainWindow..ctor() in E:\VarniApplication\PointOfSale\PointOfSale\MainWindow.xaml.cs:line 27 Inner Exception {"Unable to load the specified metadata resource."} My code: xyzEntities entites; public ctor() { entites = new xyzEntities(); //This line throws an error } I have installed sql server compact 4.0 from web installer 3.0. and added the sql server compact toolbox from the extension manager. Tell me if I am missing something to install or missing something to write code.

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  • what's a good approach to working with multiple databases?

    - by Riz
    I'm working on a project that has its own database call it InternalDb, but also it queries two other databases, call them ExternalDb1 and ExternalDb2. Both ExternalDb1 and ExternalDb2 are actually required by a few other projects. I'm wondering what the best approach for dealing with this is? Currently, I've just created a project for each of these external databases and then generated Edmx and entities using the entity-framework approach. My thought was that I could then include these projects in any of my solutions that require access to these databases. Also, I don't have any separate business layers. I just have a solution like below: Project.Domain ExternalDb1Project.Domain ExternalDb2Project.Domain Project.Web So my Domain projects contain the data access as well as the POCOs generated by Entity Framework and any business logic. But I'm not sure if this is a good approach. For example if I want to do Validation in my Project.Domain on the entities in the InternalDb, it's fine. But if I want to do Validation for entities from either of the ExternalDbs, then I wonder where it should go? To be more specific, I retrieve Employees from ExternalDb1Project.Domain. However, I want to make sure they are Active. Where should this Validation go? How to architect a project like this at a high level? Also, I want to make sure that I use IoC for my data contexts so I can create Fakes when writing tests. I wonder where the interfaces for these various data contexts would reside?

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  • What's wrong performing unit test against concrete implementation if your frameworks are not going to change?

    - by palm snow
    First a bit of background: We are re-architecting our product suite that was written 10 years ago and served its purpose. One thing that we cannot change is the database schema as we have 500+ client base using this system. Our db schema has over 150+ tables. We have decided on using Entity Framework 4.1 as DAL and still evaluating various frameworks for storing our business logic. I am investigation to bring unit testing into the mix but I also confused as to how far I need to go with setting up a full blown TDD environment. One aspect of setting up unit testing is by getting into implementing Repository, unit of work and mocking frameworks etc. This mean there will be cost and investment on the code-bloat associated with all these frameworks. I understand some of this could be auto-generated but when it comes to things like behaviors, that will be mostly hand written. Just to be clear, I am not questioning the important of unit testing your code. I am just not sure we need all its components (like repository, mocking etc.) when we are fairly certain of storage mechanism/framework (SQL Server/Entity Framework). All that code bloat with generic repositories make sense when you need a generic layers with ability to change this whenever you like however its very likely a YAGNI in our case. What we need is more of integration testing where we can unit-test our code with concrete repository objects and test data in database. In this scenario, just running integration test seem to be more beneficial in our case. Any thoughts if I am missing any thing here?

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  • Updating an Entity through a Service

    - by GeorgeK
    I'm separating my software into three main layers (maybe tiers would be a better term): Presentation ('Views') Business logic ('Services' and 'Repositories') Data access ('Entities' (e.g. ActiveRecords)) What do I have now? In Presentation, I use read-only access to Entities, returned from Repositories or Services, to display data. $banks = $banksRegistryService->getBanksRepository()->getBanksByCity( $city ); $banksViewModel = new PaginatedList( $banks ); // some way to display banks; // example, not real code I find this approach quite efficient in terms of performance and code maintanability and still safe as long as all write operations (create, update, delete) are preformed through a Service: namespace Service\BankRegistry; use Service\AbstractDatabaseService; use Service\IBankRegistryService; use Model\BankRegistry\Bank; class Service extends AbstractDatabaseService implements IBankRegistryService { /** * Registers a new Bank * * @param string $name Bank's name * @param string $bik Bank's Identification Code * @param string $correspondent_account Bank's correspondent account * * @return Bank */ public function registerBank( $name, $bik, $correspondent_account ) { $bank = new Bank(); $bank -> setName( $name ) -> setBik( $bik ) -> setCorrespondentAccount( $correspondent_account ); if( null === $this->getBanksRepository()->getDefaultBank() ) $this->setDefaultBank( $bank ); $this->getEntityManager()->persist( $bank ); return $bank; } /** * Makes the $bank system's default bank * * @param Bank $bank * @return IBankRegistryService */ public function setDefaultBank( Bank $bank ) { $default_bank = $this->getBanksRepository()->getDefaultBank(); if( null !== $default_bank ) $default_bank->setDefault( false ); $bank->setDefault( true ); return $this; } } Where am I stuck? I'm struggling about how to update certain fields in Bank Entity. Bad solution #1: Making a series of setters in Service for each setter in Bank; - seems to be quite reduntant, increases Service interface complexity and proportionally decreases it's simplicity - something to avoid if you care about code maitainability. I try to follow KISS and DRY principles. Bad solution #2: Modifying Bank directly through it's native setters; - really bad. If you'll ever need to move modification into the Service, it will be pain. Business logic should remain in Business logic layer. Plus, there are plans on logging all of the actions and maybe even involve user permissions (perhaps, through decorators) in future, so all modifications should be made only through the Service. Possible good solution: Creating an updateBank( Bank $bank, $array_of_fields_to_update) method; - makes the interface as simple as possible, but there is a problem: one should not try to manually set isDefault flag on a Bank, this operation should be performed through setDefaultBank method. It gets even worse when you have relations that you don't want to be directly modified. Of course, you can just limit the fields that can be modified by this method, but how do you tell method's user what they can and cannot modify? Exceptions?

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  • Ninject & Entity Framework =(sometimes) "The ObjectContext instance has been disposed ..."

    - by n26
    I am using Ninject and ADO.Net Entity Framework in my Aps.Net (Mvc) website. I bind the ObjectContext to Ninject using the RequestScope: Bind<Entities>().ToSelf().InRequestScope().WithConstructorArgument("connectionString", _connectionString); In most cases this works perferct. But sometimes I got the following error: The ObjectContext instance has been disposed and can no longer be used for operations that require a connection. This error occurs at different positions while getting, updating, inserting or deleting data. In some cases this error occurs until I reset my webapp and sometimes it disappears after some requests. I am displeased that I have no more details. Because it seems that there is no pattern when and where this error occurs. Because the time and position is allways different :( Some hints or ideas?

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  • Entity Framework 4 POCO entities in separate assembly, Dynamic Data Website?

    - by steve.macdonald
    Basically I want to use a dynamic data website to maintain data in an EF4 model where the entities are in their own assembly. Model and context are in another assembly. I tried this http://stackoverflow.com/questions/2282916/entity-framework-4-self-tracking-entities-asp-net-dynamic-data-error but get an "ambiguous match" error from reflection: System.Reflection.AmbiguousMatchException was unhandled by user code Message=Ambiguous match found. Source=mscorlib StackTrace: at System.RuntimeType.GetPropertyImpl(String name, BindingFlags bindingAttr, Binder binder, Type returnType, Type[] types, ParameterModifier[] modifiers) at System.Type.GetProperty(String name) at System.Web.DynamicData.ModelProviders.EFTableProvider..ctor(EFDataModelProvider dataModel, EntitySet entitySet, EntityType entityType, Type entityClrType, Type parentEntityClrType, Type rootEntityClrType, String name) at System.Web.DynamicData.ModelProviders.EFDataModelProvider.CreateTableProvider(EntitySet entitySet, EntityType entityType) at System.Web.DynamicData.ModelProviders.EFDataModelProvider..ctor(Object contextInstance, Func1 contextFactory) at System.Web.DynamicData.ModelProviders.SchemaCreator.CreateDataModel(Object contextInstance, Func1 contextFactory) at System.Web.DynamicData.MetaModel.RegisterContext(Func`1 contextFactory, ContextConfiguration configuration) at WebApplication1.Global.RegisterRoutes(RouteCollection routes) in C:\dev\Puffin\Puffin.Prototype.Web\Global.asax.cs:line 42 at WebApplication1.Global.Application_Start(Object sender, EventArgs e) in C:\dev\Puffin\Puffin.Prototype.Web\Global.asax.cs:line 78 InnerException:

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  • Entity Framework vs. nHibernate for Performance, Learning Curve overall features

    - by hadi
    I know this has been asked several times and I have read all the posts as well but they all are very old. And considering there have been advancements in versions and releases, I am hoping there might be fresh views. We are building a new application on ASP.NET MVC and need to finalize on an ORM tool. We have never used ORM before and have pretty much boiled down to two - nHibernate & Entity Framework. I really need some advice from someone who has used both these tools and can recommend based on experience. There are three points that I am focusing on to finalize - Performance Learning Curve Overall Capability Your advice will be highly appreciated. Best Regards,

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  • Entity Framework: EntityCommand automatically parsing and determine parameter types?

    - by Torben Rahbek Koch
    Hi everybody, Pretty new to Entity Framework I must admit, but I simply cannot believe that there is no built-in solution for this problem. Let's say I create an EntityCommand: EntityCommand cmd = conn.CreateCommand(); cmd.CommandType = CommandType.Text; cmd.CommandText = commandText; And let's say the the commandText is something like this: SELECT sp.UserName, sp.Rights FROM EntityContext.Users as sp WHERE sp.UserName=@UserName Now it would be really neat if the Parameters collection of cmd could be automatically filled. The framework should obviously know the types etc. but I guess that's simply not how it works beneath. The problem is that the commandText is configurable on run-time, and I must show some GUI that asks for values of the parameters. Any idea on how this could be accomplished? Thanks for any ideas and for listening!

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  • Entity Framework 4 relationship management in POCO Templates - More lazy than FixupCollection?

    - by Joe Wood
    I've been taking a look at EF4 POCO templates in beta 2. The FixupCollection looks fine for maintaining the model correctness after updating the relationship collection property (i.e. product.Orders it would set the order.Product reference ). But what about support for handling the scenario when some of those Order objects are removed from the context? The use-case of maintaining cascading deletes in the in-memory model. The old Typed DataSet model used to do this by performing the query through the container to derive the relationship results. Like the DataSet, this would require a reference to the ObjectContext inside the entity class so that it could query the top-level Order collection. Better support for Separation of Concerns in the ObjectContext would be required. It looks like EF is not suited to this use-case that DataSets did out of the box.... am I right?

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  • Why does a newly created EF-entity throw an ID is null exception when trying to save?

    - by Richard
    I´m trying out entity framework included in VS2010 but ´ve hit a problem with my database/model generated from the graphical interface. When I do: user = dataset.UserSet.CreateObject(); user.Id = Guid.NewGuid(); dataset.UserSet.AddObject(user); dataset.SaveChanges(); {"Cannot insert the value NULL into column 'Id', table 'BarSoc2.dbo.UserSet'; column does not allow nulls. INSERT fails.\r\nThe statement has been terminated."} The table i´m inserting into looks like so: -- Creating table 'UserSet' CREATE TABLE [dbo].[UserSet] ( [Id] uniqueidentifier NOT NULL, [Name] nvarchar(max) NOT NULL, [Username] nvarchar(max) NOT NULL, [Password] nvarchar(max) NOT NULL ); GO -- Creating primary key on [Id] in table 'UserSet' ALTER TABLE [dbo].[UserSet] ADD CONSTRAINT [PK_UserSet] PRIMARY KEY CLUSTERED ([Id] ASC); GO Am I creating the object in the wrong way or doing something else basic wrong?

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  • 3 methods for adding a "Product" through Entity Framework. What's the difference?

    - by Kohan
    Reading this MSDN article titled "Working with ObjectSet (Entity Framework)" It shows two examples on how to add a Product.. one for 3.5 and another for 4.0. http://msdn.microsoft.com/en-us/library/ee473442.aspx Through my lack of knowledge I am possibly completely missing something here, but i never added a Product like this: //In .NET Framework 3.5 SP1, use the following code: (ObjectQuery) using (AdventureWorksEntities context = new AdventureWorksEntities()) { // Add the new object to the context. context.AddObject("Products", newProduct); } //New in .NET Framework 4, use the following code: (ObjectSet) using (AdventureWorksEntities context = new AdventureWorksEntities()) { // Add the new object to the context. context.Products.AddObject(newProduct); } I would not have done it either way and just used: // (My familiar way) using (AdventureWorksEntities context = new AdventureWorksEntities()) { // Add the new object to the context. context.AddToProducts(newProduct); } What's the difference between these three ways? Is "My way" just another way of using an ObjectQuery? Thanks, Kohan

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  • Entity Framework - Why does EF use LEFT OUTER JOIN's in a 1-to-1 join?

    - by Taylor L
    Why does .NET Entity Framework produce SQL that uses a subquery and left outer join on a simple 1-to-1 relationship? I expected to see a simple join on the two tables. I'm using Devart Dotconnect for Oracle. Any ideas? Below is the output I see courtesy of the EFTracingProvider: SELECT 1 AS C1, "Join1".USER_ID1 AS USER_ID, ... FROM "MY$NAMESPACE".MYTABLE1 "Extent1" INNER JOIN (... FROM "MY$NAMESPACE".MYTABLE2 "Extent2" LEFT OUTER JOIN "MY$NAMESPACE".MYTABLE1 "Extent3" ON "Extent2".OTHER_ID = "Extent3".OTHER_ID ) "Join1" ON "Extent1".OTHER_ID = "Join1".OTHER_ID1 WHERE "Extent1".USER_ID = :EntityKeyValue1 -- EntityKeyValue1 (dbtype=String, size=6, direction=Input) = "000000"

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