Search Results

Search found 9916 results on 397 pages for 'entity component'.

Page 96/397 | < Previous Page | 92 93 94 95 96 97 98 99 100 101 102 103  | Next Page >

• Would you allow this type of query?

  - by user564577

  I'm exploring using an ORM tool in our development shop, and in particular Entity Framework 4.0. Since we work with VERY large databases, I'm a bit concerned about the query's it generates. Doing something simple like getting clients with an address in a state looks like below. As a database developer or admin would you allow this? Is it as bad as it looks? Assume every join is on a clustered index. SELECT [Project2].[ClientKey] AS [ClientKey], [Project2].[FirstName] AS [FirstName], [Project2].[LastName] AS [LastName], [Project2].[IsEnabled] AS [IsEnabled], [Project2].[ChangeUser] AS [ChangeUser], [Project2].[ChangeDate] AS [ChangeDate], [Project2].[C1] AS [C1], [Project2].[AddressKey] AS [AddressKey], [Project2].[ClientKey1] AS [ClientKey1], [Project2].[AddressTypeCode] AS [AddressTypeCode], [Project2].[PrimaryAddress] AS [PrimaryAddress], [Project2].[AddressLine1] AS [AddressLine1], [Project2].[AddressLine2] AS [AddressLine2], [Project2].[City] AS [City], [Project2].[State] AS [State], [Project2].[ZIP] AS [ZIP] FROM ( SELECT [Distinct1].[ClientKey] AS [ClientKey], [Distinct1].[FirstName] AS [FirstName], [Distinct1].[LastName] AS [LastName], [Distinct1].[IsEnabled] AS [IsEnabled], [Distinct1].[ChangeUser] AS [ChangeUser], [Distinct1].[ChangeDate] AS [ChangeDate], [Extent3].[AddressKey] AS [AddressKey], [Extent3].[ClientKey] AS [ClientKey1], [Extent3].[AddressTypeCode] AS [AddressTypeCode], [Extent3].[PrimaryAddress] AS [PrimaryAddress], [Extent3].[AddressLine1] AS [AddressLine1], [Extent3].[AddressLine2] AS [AddressLine2], [Extent3].[City] AS [City], [Extent3].[State] AS [State], [Extent3].[ZIP] AS [ZIP], CASE WHEN ([Extent3].[AddressKey] IS NULL) THEN CAST(NULL AS int) ELSE 1 END AS [C1] FROM (SELECT DISTINCT [Extent1].[ClientKey] AS [ClientKey], [Extent1].[FirstName] AS [FirstName], [Extent1].[LastName] AS [LastName], [Extent1].[IsEnabled] AS [IsEnabled], [Extent1].[ChangeUser] AS [ChangeUser], [Extent1].[ChangeDate] AS [ChangeDate] FROM [Common].[Clients] AS [Extent1] INNER JOIN [Common].[ClientAddresses] AS [Extent2] ON [Extent1].[ClientKey] = [Extent2].[ClientKey] WHERE (( CAST(CHARINDEX(UPPER('D'), UPPER([Extent1].[LastName])) AS int)) > 0) AND ([Extent1].[IsEnabled] = 1) AND ([Extent2].[City] IS NOT NULL) AND ((UPPER([Extent2].[City])) = (UPPER('Colorado Springs'))) ) AS [Distinct1] LEFT OUTER JOIN [Common].[ClientAddresses] AS [Extent3] ON [Distinct1].[ClientKey] = [Extent3].[ClientKey] ) AS [Project2] ORDER BY [Project2].[ClientKey] ASC, [Project2].[FirstName] ASC, [Project2].[LastName] ASC, [Project2].[IsEnabled] ASC, [Project2].[ChangeUser] ASC, [Project2].[ChangeDate] ASC, [Project2].[C1] ASC

  Read the article

• EF Code First, how can I achieve two foreign keys from one table to other table?

  - by Yoo Matsuo

  I've recently downloaded Entity Framework Code First CTP5, and have a trouble with this scenario. I have two tables as follows: Members table ID Name Comments table ID Comment CommentedMemberID CommentMemberID And, the data should be like the following: Members ID Name 1 Mike 2 John 3 Tom Comments ID Comment CommentedMemberID CommentMemberID 1 Good 1 2 2 Good 1 3 3 Bad 2 1 Then, I coded as shown below: public class Member { public int ID {get; set; } public string Name { get; set;} public virtual ICollection Comments { get; set;} } public class Comment { public int ID { get; set; } public string Comment { get; set; } public int CommentedMemberID { get; set; } public int CommentMemberID{ get; set; } public virtual Member CommentedMember { get; set; } public virtual Member CommentMember { get; set; } } public class TestContext : DbContext { public DbSet Members { get; set; } public DbSet Comments { get; set; } } But when I run these models on my cshtml, it gives me errors saying "Cannot create CommentMember instance" or something like that (Sorry, I already changed my models to proceed the EF Code First evaluation, so can't reproduce the same error). I've also tried to use OnModelCreating on the TestContext, but can't find any good instructions and don't know what to do. I saw a blog post of the EF Code First CTP3, and it seems there was a RelatedTo attribute in that version, but now it has gone. Could anyone know how to get it work properly? Or is this a totally wrong way to go with this scenario? Thanks, Yoo

  Read the article

• Hibernate OneToMany and ManyToOne confusion! Null List!

  - by squizz

  I have two tables... For example - Company and Employee (let's keep this real simple) Company( id, name ); Employee( id, company_id ); Employee.company_id is a foreign key. My entity model looks like this... Employee @ManyToOne(cascade = CascadeType.PERSIST) @JoinColumn(name = "company_id") Company company; Company @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER) @JoinColumn(name = "company_id") List<Employee> employeeList = new ArrayList<Employee>(); So, yeah I want a list of employees for a company. When I do the following... Employee e = new Employee(); e.setCompany(c); //c is an Company that is already in the database. DAO.insertEmployee(e); //this works fine! If I then get my Company object it's list is empty! Ive tried endless different ways from the Hibernate documentation! Obviously not tried the correct one yet! I just want the list to be populated for me or find out a sensible alternative. Help would be greatly appreciated, thanks!

  Read the article

• EventHandlers saved to databases.

  - by Stacey

  In a database application (using Sql Server right now, in C#, with Entity Framework 4.0) I have a situation where I need to trigger events when some values change. For instance assume a class "Trackable". class Trackable { string Name { get; set; } int Positive { get; set; } int Negative { get; set; } int Total { get; set; } // event OnChanged } Trackable is represented in the database as follows; table Trackables Id | guid name | varchar(32) positive | int negative | int Total is of course, calculated at runtime. When a trackable event changes, I want to inspect its previous value, and then see what it is changing to, and be capable of reacting accordingly. However different trackables need to trigger different events (to avoid a huge, massive cascading switch/if block). If this were just only C# code it would be easy - but they have to be saved to the database. I can't divide up each different trackable into a different table/class, that would be silly - they are all identical, but the event raised is different based on how they are made. So I guess my question is, is there any way to store an event handler in a database such that.. Trackable t1 = new Trackable() { Name = "Trackable1" OnChange += TrackableChangedEventHandler(OnTrackable1Change) } Trackable t2 = new Trackable() { Name = "Trackable2", OnChange += TrackableChangedEventHandler(OnTrackable2Change) }

  Read the article

• Bind data of interface properties only

  - by nivpenso

  I am new in all the Entity Framework models and the data bindings. I created an interface and generated a model class from my Candidate table in the db. public interface ICandidate { String ID { get; set; } string Name { get; set; } string Mail { get; set; } } i created a partial class to the generated Candidate model so i will be able to implement the ICandidate interface without changing any generated code. public partial class Candidates : ICandidate { string ICandidate.ID { get { return this.PK; } set { _PK = value; } } string ICandidate.Name { get{ return this._Name; } set { _Name = value; } } string ICandidate.Mail { get { return this._Email; } set { this._Email = value; } } } Of course, the generated class has more properties than the interface has (Like IsDeleted field that is not necessary for the interface). I want to display in a DataGridView all the candidates from the db. But I want that only the interface's properties will be shown as columns in the DataGridView. Is there a way bind only the interface's properties the the DataGridView? In my DB there is a table called Candidate_To_Company with these columns: PK, Candidate_FK, Company_FK, Insertion_Date I would like to bind this table to DataGridView. but instead of displaying Candidate_FK i would like to display the candidate name from ICandidate. Is this possible?

  Read the article

• How to decide whether to implement an operation as Entity operation vs Service operation in Domain Driven Design?

  - by Louis Rhys

  I am reading Evans's Domain Driven Design. The book says that there are entity and there are services. If I were to implement an operation, how to decide whether I should add it as a method on an entity or do it in a service class? e.g. myEntity.DoStuff() or myService.DoStuffOn(myEntity)? Does it depend on whether other entities are involved? If it involves other entities, implement as service operation? But entities can have associations and can traverse it from there too right? Does it depend on stateless or not? But service can also access entities' variable, right? Like in do stuff myService.DoStuffOn, it can have code like if(myEntity.IsX) doSomething(); Which means that it will depend on the state? Or does it depend on complexity? How do you define complex operations?

  Read the article

• How do I best remove an entity from my game loop when it is dead?

  - by Iain

  Ok so I have a big list of all my entities which I loop through and update. In AS3 I can store this as an Array (dynamic length, untyped), a Vector (typed) or a linked list (not native). At the moment I'm using Array but I plan to change to Vector or linked list if it is faster. Anyway, my question, when an Entity is destroyed, how should I remove it from the list? I could null its position, splice it out or just set a flag on it to say "skip over me, I'm dead." I'm pooling my entities, so an Entity that is dead is quite likely to be alive again at some point. For each type of collection what is my best strategy, and which combination of collection type and removal method will work best?

  Read the article

• Why does Linq to Entity Sum return null when the list is empty?

  - by Hannele

  There are quite a few questions on Stack Overflow about the Linq to Entity / Linq to SQL Sum extension method, about how it returns null when the result set is empty: 1, 2, 3, 4, 5, 6, 7, and many more, as well as a blog post discussing the issue here. Now, I could go a flag these as duplicates, but I feel it is still an inconsistency in the Linq implementation. I am assuming at this point that it is not a bug, but is more or less working as designed. I understand that there are workarounds (for example, casting the field to a nullable type, so you can coalesce with ??), and I also understand that for the underlying SQL, a NULL result is expected for an empty list. But because the result of the Sum extension for nullable types is also not nullable, why would the Linq to SQL / Linq to Entity Sum have been designed to behave this way?

  Read the article

• Why does Linq to Entity Sum return null when the result set is empty?

  - by Hannele

  There are quite a few questions on Stack Overflow about the Linq to Entity / Linq to SQL Sum extension method, about how it returns null when the result set is empty: 1, 2, 3, 4, 5, 6, 7, and many more, as well as a blog post discussing the issue here. I feel it is an inconsistency in the Linq implementation. I am assuming at this point that it is not a bug, but is more or less working as designed. I understand that there are workarounds (for example, casting the field to a nullable type, so you can coalesce with ??), and I also understand that for the underlying SQL, a NULL result is expected for an empty result set. But because the result of the Sum extension for non-nullable types is also non-nullable, why does the Linq to SQL / Linq to Entity Sum behave this way?

  Read the article

• linq-to-sql "an attempt has been made to attach or add an entity that is not new"?

  - by Curtis White

  I've been getting several errors: cannot add an entity with a key that is already in use An attempt has been made to attach or add an entity that is not new, perhaps having been loaded from another datacontext In case 1, this stems from trying to set the key for an entity versus the entity. In case 2, I'm not attaching an entity but I am doing this: MyParent.Child = EntityFromOtherDataContext; I've been using using the pattern of wrap everything with a using datacontext. In my case, I am using this in a web forms scenario, and obviously moving the datacontext object to a class wide member variables solves this. My questions are thus 2 fold: How can I get rid of these errors and not have to structure my program in an odd way or pass the datacontext around while keeping the local-wrap pattern? I assume I could make another hit to the database but that seems very inefficient. Would most people recommend that moving the datacontext to the class wide scope is desirable for web pages?

  Read the article

• Binding a wpf listbox to a combobox

  - by user293545

  Hi there, I have created a very basic wpf application that I want to use to record time entries against different projects. I havent used mvvm for this as I think its an overkill. I have a form that contains a combobox and a listbox. I have created a basic entity model like this What I am trying to do is bind the combobox to Project and whenever I select an item from the combobox it updates the listview with the available tasks associated with that project. This is my xaml so far. I dont have any code behind as I have simply clicked on that Data menu and then datasources and dragged and dropped the items over. The application loads ok and the combobox is been populated however nothing is displaying in the listbox. Can anyone tell me what I have missed? <Window.Resources> <CollectionViewSource x:Key="tasksViewSource" d:DesignSource="{d:DesignInstance l:Task, CreateList=True}" /> <CollectionViewSource x:Key="projectsViewSource" d:DesignSource="{d:DesignInstance l:Project, CreateList=True}" /> </Window.Resources> <Grid DataContext="{StaticResource tasksViewSource}"> <l:NotificationAreaIcon Text="Time Management" Icon="Resources\NotificationAreaIcon.ico" MouseDoubleClick="OnNotificationAreaIconDoubleClick"> <l:NotificationAreaIcon.MenuItems> <forms:MenuItem Text="Open" Click="OnMenuItemOpenClick" DefaultItem="True" /> <forms:MenuItem Text="-" /> <forms:MenuItem Text="Exit" Click="OnMenuItemExitClick" /> </l:NotificationAreaIcon.MenuItems> </l:NotificationAreaIcon> <Button Content="Insert" Height="23" HorizontalAlignment="Left" Margin="150,223,0,0" Name="btnInsert" VerticalAlignment="Top" Width="46" Click="btnInsert_Click" /> <ComboBox Height="23" HorizontalAlignment="Left" Margin="70,16,0,0" Name="comProjects" VerticalAlignment="Top" Width="177" DisplayMemberPath="Project1" ItemsSource="{Binding Source={StaticResource projectsViewSource}}" SelectedValuePath="ProjectID" /> <Label Content="Projects" Height="28" HorizontalAlignment="Left" Margin="12,12,0,0" Name="label1" VerticalAlignment="Top" IsEnabled="False" /> <Label Content="Tasks" Height="28" HorizontalAlignment="Left" Margin="16,61,0,0" Name="label2" VerticalAlignment="Top" /> <ListBox Height="112" HorizontalAlignment="Left" Margin="16,87,0,0" Name="lstTasks" VerticalAlignment="Top" Width="231" DisplayMemberPath="Task1" ItemsSource="{Binding Path=ProjectID, Source=comProjects}" SelectedValuePath="TaskID" /> <TextBox Height="23" HorizontalAlignment="Left" Margin="101,224,0,0" Name="txtMinutes" VerticalAlignment="Top" Width="42" /> <Label Content="Mins to Insert" Height="28" HorizontalAlignment="Left" Margin="12,224,0,0" Name="label3" VerticalAlignment="Top" /> <Button Content="None" Height="23" HorizontalAlignment="Left" Margin="203,223,0,0" Name="btnNone" VerticalAlignment="Top" Width="44" /> </Grid>

  Read the article

• EF4: ObjectContext inconsistent when inserting into a view with triggers

  - by user613567

  I get an Invalid Operation Exception when inserting records in a View that uses “Instead of” triggers in SQL Server with ADO.NET Entity Framework 4. The error message says: {"The changes to the database were committed successfully, but an error occurred while updating the object context. The ObjectContext might be in an inconsistent state. Inner exception message: The key-value pairs that define an EntityKey cannot be null or empty. Parameter name: record"} @ at System.Data.Objects.ObjectContext.SaveChanges(SaveOptions options) at System.Data.Objects.ObjectContext.SaveChanges() In this simplified example I created two tables, Contacts and Employers, and one view Contacts_x_Employers which allows me to insert or retrieve rows into/from these two tables at once. The Tables only have a Name and an ID attributes and the view is based on a join of both: CREATE VIEW [dbo].[Contacts_x_Employers] AS SELECT dbo.Contacts.ContactName, dbo.Employers.EmployerName FROM dbo.Contacts INNER JOIN dbo.Employers ON dbo.Contacts.EmployerID = dbo.Employers.EmployerID And has this trigger: Create TRIGGER C_x_E_Inserts ON Contacts_x_Employers INSTEAD of INSERT AS BEGIN SET NOCOUNT ON; insert into Employers (EmployerName) select i.EmployerName from inserted i where not i.EmployerName in (select EmployerName from Employers) insert into Contacts (ContactName, EmployerID) select i.ContactName, e.EmployerID from inserted i inner join employers e on i.EmployerName = e.EmployerName; END GO The .NET Code follows: using (var Context = new TriggersTestEntities()) { Contacts_x_Employers CE1 = new Contacts_x_Employers(); CE1.ContactName = "J"; CE1.EmployerName = "T"; Contacts_x_Employers CE2 = new Contacts_x_Employers(); CE1.ContactName = "W"; CE1.EmployerName = "C"; Context.Contacts_x_Employers.AddObject(CE1); Context.Contacts_x_Employers.AddObject(CE2); Context.SaveChanges(); //? line with error } SSDL and CSDL (the view nodes): <EntityType Name="Contacts_x_Employers"> <Key> <PropertyRef Name="ContactName" /> <PropertyRef Name="EmployerName" /> </Key> <Property Name="ContactName" Type="varchar" Nullable="false" MaxLength="50" /> <Property Name="EmployerName" Type="varchar" Nullable="false" MaxLength="50" /> </EntityType> <EntityType Name="Contacts_x_Employers"> <Key> <PropertyRef Name="ContactName" /> <PropertyRef Name="EmployerName" /> </Key> <Property Name="ContactName" Type="String" Nullable="false" MaxLength="50" Unicode="false" FixedLength="false" /> <Property Name="EmployerName" Type="String" Nullable="false" MaxLength="50" Unicode="false" FixedLength="false" /> </EntityType> The Visual Studio solution and the SQL Scripts to re-create the whole application can be found in the TestViewTrggers.zip at ftp://JulioSantos.com/files/TriggerBug/. I appreciate any assistance that can be provided. I already spent days working on this problem.

  Read the article

• How to reflect over T to build an expression tree for a query?

  - by Alex

  Hi all, I'm trying to build a generic class to work with entities from EF. This class talks to repositories, but it's this class that creates the expressions sent to the repositories. Anyway, I'm just trying to implement one virtual method that will act as a base for common querying. Specifically, it will accept a an int and it only needs to perform a query over the primary key of the entity in question. I've been screwing around with it and I've built a reflection which may or may not work. I say that because I get a NotSupportedException with a message of LINQ to Entities does not recognize the method 'System.Object GetValue(System.Object, System.Object[])' method, and this method cannot be translated into a store expression. So then I tried another approach and it produced the same exception but with the error of The LINQ expression node type 'ArrayIndex' is not supported in LINQ to Entities. I know it's because EF will not parse the expression the way L2S will. Anyway, I'm hopping someone with a bit more experience can point me into the right direction on this. I'm posting the entire class with both attempts I've made. public class Provider<T> where T : class { protected readonly Repository<T> Repository = null; private readonly string TEntityName = typeof(T).Name; [Inject] public Provider( Repository<T> Repository) { this.Repository = Repository; } public virtual void Add( T TEntity) { this.Repository.Insert(TEntity); } public virtual T Get( int PrimaryKey) { // The LINQ expression node type 'ArrayIndex' is not supported in // LINQ to Entities. return this.Repository.Select( t => (((int)(t as EntityObject).EntityKey.EntityKeyValues[0].Value) == PrimaryKey)).Single(); // LINQ to Entities does not recognize the method // 'System.Object GetValue(System.Object, System.Object[])' method, // and this method cannot be translated into a store expression. return this.Repository.Select( t => (((int)t.GetType().GetProperties().Single( p => (p.Name == (this.TEntityName + "Id"))).GetValue(t, null)) == PrimaryKey)).Single(); } public virtual IList<T> GetAll() { return this.Repository.Select().ToList(); } protected virtual void Save() { this.Repository.Update(); } }

  Read the article

• how a custom BizTalk pipeline component can be used to split an incoming message into smaller indivi

  Use a custom pipeline component to split an incoming message into smaller individual messages for further processing. Sample shows how to use simple but powerful techniques that can be built upon and developed for use in a production environment  read moreBy BiZTech KnowDid 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.

  Read the article

• A TDD Journey: 4-Tests as Documentation; False Positive Results; Component Isolation

  In Test-Driven Development (TDD) , The writing of a unit test is done more to design and to document than to verifiy. By writing a unit test you close a number of feedback loops, and verifying the functionality of the code is just a minor one. everything you need to know about your class under test is embodied in a simple list of the names of the tests. Michael Sorens continues his introduction to TDD that is more of a journey in six parts, by discussing Tests as Documentation, False Positive Results and Component Isolation.

  Read the article

• WCF Data Service BeginSaveChanges not saving changes in Silverlight app

  - by Enigmativity

  I'm having a hell of a time getting WCF Data Services to work within Silverlight. I'm using the VS2010 RC. I've struggled with the cross domain issue requiring the use of clientaccesspolicy.xml & crossdomain.xml files in the web server root folder, but I just couldn't get this to work. I've resorted to putting both the Silverlight Web App & the WCF Data Service in the same project to get past this issue, but any advice here would be good. But now that I can actually see my data coming from the database and being displayed in a data grid within Silverlight I thought my troubles were over - but no. I can edit the data and the in-memory entity is changing, but when I call BeginSaveChanges (with the appropriate async EndSaveChangescall) I get no errors, but no data updates in the database. Here's my WCF Data Services code: public class MyDataService : DataService<MyEntities> { public static void InitializeService(DataServiceConfiguration config) { config.SetEntitySetAccessRule("*", EntitySetRights.All); config.SetServiceOperationAccessRule("*", ServiceOperationRights.All); config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V2; } protected override void OnStartProcessingRequest(ProcessRequestArgs args) { base.OnStartProcessingRequest(args); HttpContext context = HttpContext.Current; HttpCachePolicy c = HttpContext.Current.Response.Cache; c.SetCacheability(HttpCacheability.ServerAndPrivate); c.SetExpires(HttpContext.Current.Timestamp.AddSeconds(60)); c.VaryByHeaders["Accept"] = true; c.VaryByHeaders["Accept-Charset"] = true; c.VaryByHeaders["Accept-Encoding"] = true; c.VaryByParams["*"] = true; } } I've pinched the OnStartProcessingRequest code from Scott Hanselman's article Creating an OData API for StackOverflow including XML and JSON in 30 minutes. Here's my code from my Silverlight app: private MyEntities _wcfDataServicesEntities; private CollectionViewSource _customersViewSource; private ObservableCollection<Customer> _customers; private void UserControl_Loaded(object sender, RoutedEventArgs e) { if (!System.ComponentModel.DesignerProperties.GetIsInDesignMode(this)) { _wcfDataServicesEntities = new MyEntities(new Uri("http://localhost:7156/MyDataService.svc/")); _customersViewSource = this.Resources["customersViewSource"] as CollectionViewSource; DataServiceQuery<Customer> query = _wcfDataServicesEntities.Customer; query.BeginExecute(result => { _customers = new ObservableCollection<Customer>(); Array.ForEach(query.EndExecute(result).ToArray(), _customers.Add); Dispatcher.BeginInvoke(() => { _customersViewSource.Source = _customers; }); }, null); } } private void button1_Click(object sender, RoutedEventArgs e) { _wcfDataServicesEntities.BeginSaveChanges(r => { var response = _wcfDataServicesEntities.EndSaveChanges(r); string[] results = new[] { response.BatchStatusCode.ToString(), response.IsBatchResponse.ToString() }; _customers[0].FinAssistCompanyName = String.Join("|", results); }, null); } The response string I get back data binds to my grid OK and shows "-1|False". My intent is to get a proof-of-concept working here and then do the appropriate separation of concerns to turn this into a simple line-of-business app. I've spent hours and hours on this. I'm being driven insane. Any ideas how to get this working?

  Read the article

• help with xml parsing using php

  - by fayer

  i've got following example xml: <entity id="1"> <name>computer</name> <type>category</type> <entities> <entity id="2"> <name>mac</name> <type>category</type> </entity> <entity id="3"> <name>linux</name> <type>category</type> <entities> <entity id="4"> <name>ubuntu</name> <type>category</type> </entity> <entity id="5"> <name>redhat</name> <type>category</type> <entities> <entity id="6"> <name>server</name> <type>category</type> </entity> <entity id="7"> <name>desktop</name> <type>category</type> </entity> </entities> </entity> </entities> </entity> </entities> </entity> if i've got an id, lets say 5. is it possible to retrieve the following: the name of the entity with the id=5 (redhat) ALL the child entities and their name and id (server/6 and desktop/7) all the parent entities and their name and id (computer/1, mac/2 and linux/3) im a noob on parsing xml. is this accomplished by xpath only or xquery/xpath? i would appreciate if someone could give me some example code to do this with simplexml. thanks!

  Read the article

• C# asp.net EF MVC postgresql error 23505: Duplicate key violates unique constraint

  - by user2721755

  EDIT: It was issue with database table - dropping and recreating table id column did the work. Problem solved. I'm trying to build web application, that is connected to postgresql database. Results are displaying in view with Kendo UI. When I'm trying to add new row (with Kendo UI 'Add new record' button), I get error 23505: 'Duplicate key violates unique constraint'. My guess is, that EF takes id to insert from the beginning, not the last one, because after 35 (it's number of rows in table) tries - and errors - adding works perfectly. Can someone help me to understand, what's wrong? Model: using System.ComponentModel.DataAnnotations; using System.ComponentModel.DataAnnotations.Schema; namespace MainConfigTest.Models { [Table("mainconfig", Schema = "public")] public class Mainconfig { [Column("id")] [Key] [Editable(false)] public int Id { get; set; } [Column("descr")] [Editable(true)] public string Descr { get; set; } [Column("hibversion")] [Required] [Editable(true)] public long Hibversion { get; set; } [Column("mckey")] [Required] [Editable(true)] public string Mckey { get; set; } [Column("valuexml")] [Editable(true)] public string Valuexml { get; set; } [Column("mcvalue")] [Editable(true)] public string Mcvalue { get; set; } } } Context: using System.Data.Entity; namespace MainConfigTest.Models { public class MainConfigContext : DbContext { public DbSet<Mainconfig> Mainconfig { get; set; } } } Controller: namespace MainConfigTest.Controllers { public class MainConfigController : Controller { #region Properties private Models.MainConfigContext db = new Models.MainConfigContext(); private string mainTitle = "Mainconfig (Kendo UI)"; #endregion #region Initialization public MainConfigController() { ViewBag.MainTitle = mainTitle; } #endregion #region Ajax [HttpGet] public JsonResult GetMainconfig() { int take = HttpContext.Request["take"] == null ? 5 : Convert.ToInt32(HttpContext.Request["take"]); int skip = HttpContext.Request["skip"] == null ? 0 : Convert.ToInt32(HttpContext.Request["skip"]); Array data = (from Models.Mainconfig c in db.Mainconfig select c).OrderBy(c => c.Id).ToArray().Skip(skip).Take(take).ToArray(); return Json(new Models.MainconfigResponse(data, db.Mainconfig.Count()), JsonRequestBehavior.AllowGet); } [HttpPost] public JsonResult Create() { try { Mainconfig itemToAdd = new Mainconfig() { Descr = Convert.ToString(HttpContext.Request["Descr"]), Hibversion = Convert.ToInt64(HttpContext.Request["Hibversion"]), Mckey = Convert.ToString(HttpContext.Request["Mckey"]), Valuexml = Convert.ToString(HttpContext.Request["Valuexml"]), Mcvalue = Convert.ToString(HttpContext.Request["Mcvalue"]) }; db.Mainconfig.Add(itemToAdd); db.SaveChanges(); return Json(new { Success = true }); } catch (InvalidOperationException ex) { return Json(new { Success = false, msg = ex }); } } //other methods } } Kendo UI script in view: <script type="text/javascript"> $(document).ready(function () { $("#config-grid").kendoGrid({ sortable: true, pageable: true, scrollable: false, toolbar: ["create"], editable: { mode: "popup" }, dataSource: { pageSize: 5, serverPaging: true, transport: { read: { url: '@Url.Action("GetMainconfig")', dataType: "json" }, update: { url: '@Url.Action("Update")', type: "Post", dataType: "json", complete: function (e) { $("#config-grid").data("kendoGrid").dataSource.read(); } }, destroy: { url: '@Url.Action("Delete")', type: "Post", dataType: "json" }, create: { url: '@Url.Action("Create")', type: "Post", dataType: "json", complete: function (e) { $("#config-grid").data("kendoGrid").dataSource.read(); } }, }, error: function (e) { if(e.Success == false) { this.cancelChanges(); } }, schema: { data: "Data", total: "Total", model: { id: "Id", fields: { Id: { editable: false, nullable: true }, Descr: { type: "string"}, Hibversion: { type: "number", validation: {required: true,}, }, Mckey: { type: "string", validation: { required: true, }, }, Valuexml:{ type: "string"}, Mcvalue: { type: "string" } } } } }, //end DataSource // generate columns etc. Mainconfig table structure: id serial NOT NULL, descr character varying(200), hibversion bigint NOT NULL, mckey character varying(100) NOT NULL, valuexml character varying(8000), mcvalue character varying(200), CONSTRAINT mainconfig_pkey PRIMARY KEY (id), CONSTRAINT mainconfig_mckey_key UNIQUE (mckey) Any help will be appreciated.

  Read the article

• iPhone Development - Query related records using CoreData

  - by Mustafa

  I have a case where i have three entities with one-to-many and one-to-many relationships: Entity A (Entity B relationhip), Entity B (Entity A relationship, Entity C relationship), Entity C (Entity B relationhip) I have the reference of Entity A, and now i want to fetch all the related Entity C records. How can i do that? (with least amount of code) Edit: Here's another way to put it. Can we perform joins with CoreData. For example, (and this is a very crude example), We have a following entity-relationship: Grand Parent (1)---(m) Parent Parent (1)---(m) Child So, now if i have "Albert" the Grand Parent, and i want to get all his grand children, how can i do that?

  Read the article

• ODI 12c - Aggregating Data

  - by David Allan

  This posting will look at the aggregation component that was introduced in ODI 12c. For many ETL tool users this shouldn't be a big surprise, its a little different than ODI 11g but for good reason. You can use this component for composing data with relational like operations such as sum, average and so forth. Also, Oracle SQL supports special functions called Analytic SQL functions, you can use a specially configured aggregation component or the expression component for these now in ODI 12c. In database systems an aggregate transformation is a transformation where the values of multiple rows are grouped together as input on certain criteria to form a single value of more significant meaning - that's exactly the purpose of the aggregate component. In the image below you can see the aggregate component in action within a mapping, for how this and a few other examples are built look at the ODI 12c Aggregation Viewlet here - the viewlet illustrates a simple aggregation being built and then some Oracle analytic SQL such as AVG(EMP.SAL) OVER (PARTITION BY EMP.DEPTNO) built using both the aggregate component and the expression component. In 11g you used to just write the aggregate expression directly on the target, this made life easy for some cases, but it wan't a very obvious gesture plus had other drawbacks with ordering of transformations (agg before join/lookup. after set and so forth) and supporting analytic SQL for example - there are a lot of postings from creative folks working around this in 11g - anything from customizing KMs, to bypassing aggregation analysis in the ODI code generator. The aggregate component has a few interesting aspects. 1. Firstly and foremost it defines the attributes projected from it - ODI automatically will perform the grouping all you do is define the aggregation expressions for those columns aggregated. In 12c you can control this automatic grouping behavior so that you get the code you desire, so you can indicate that an attribute should not be included in the group by, that's what I did in the analytic SQL example using the aggregate component. 2. The component has a few other properties of interest; it has a HAVING clause and a manual group by clause. The HAVING clause includes a predicate used to filter rows resulting from the GROUP BY clause. Because it acts on the results of the GROUP BY clause, aggregation functions can be used in the HAVING clause predicate, in 11g the filter was overloaded and used for both having clause and filter clause, this is no longer the case. If a filter is after an aggregate, it is after the aggregate (not sometimes after, sometimes having).  3. The manual group by clause let's you use special database grouping grammar if you need to. For example Oracle has a wealth of highly specialized grouping capabilities for data warehousing such as the CUBE function. If you want to use specialized functions like that you can manually define the code here. The example below shows the use of a manual group from an example in the Oracle database data warehousing guide where the SUM aggregate function is used along with the CUBE function in the group by clause. The SQL I am trying to generate looks like the following from the data warehousing guide; SELECT channel_desc, calendar_month_desc, countries.country_iso_code,       TO_CHAR(SUM(amount_sold), '9,999,999,999') SALES$ FROM sales, customers, times, channels, countries WHERE sales.time_id=times.time_id AND sales.cust_id=customers.cust_id AND   sales.channel_id= channels.channel_id  AND customers.country_id = countries.country_id  AND channels.channel_desc IN   ('Direct Sales', 'Internet') AND times.calendar_month_desc IN   ('2000-09', '2000-10') AND countries.country_iso_code IN ('GB', 'US') GROUP BY CUBE(channel_desc, calendar_month_desc, countries.country_iso_code); I can capture the source datastores, the filters and joins using ODI's dataset (or as a traditional flow) which enables us to incrementally design the mapping and the aggregate component for the sum and group by as follows; In the above mapping you can see the joins and filters declared in ODI's dataset, allowing you to capture the relationships of the datastores required in an entity-relationship style just like ODI 11g. The mix of ODI's declarative design and the common flow design provides for a familiar design experience. The example below illustrates flow design (basic arbitrary ordering) - a table load where only the employees who have maximum commission are loaded into a target. The maximum commission is retrieved from the bonus datastore and there is a look using employees as the driving table and only those with maximum commission projected. Hopefully this has given you a taster for some of the new capabilities provided by the aggregate component in ODI 12c. In summary, the actions should be much more consistent in behavior and more easily discoverable for users, the use of the components in a flow graph also supports arbitrary designs and the tool (rather than the interface designer) takes care of the realization using ODI's knowledge modules. Interested to know if a deep dive into each component is interesting for folks. Any thoughts? 

  Read the article

• Different setter behavior between DbContext and ObjectContext

  - by Paul

  (This is using EntityFramework 4.2 CTP) I haven't found any references to this on the web yet, although it's likely I'm using the wrong terminology while searching. There's also a very likely scenario where this is 100% expected behavior, just looking for confirmation and would rather not dig through the tt template (still new to this). Assuming I have a class with a boolean field called Active and I have one row that already has this value set to true. I have code that executes to set said field to True regardless of it's existing value. If I use DbContext to update the value to True no update is made. If I use ObjectContext to update the value an update is made regardless of the existing value. This is happening in the exact same EDMX, all I did was change the code generation template from DbContext to EntityObject. Update: Ok, found the confirmation I was looking for...consider this a dupe...next time I'll do MOAR SEARCHING! Entity Framework: Cancel a property change if no change in value ** Update 2: ** Problem: the default tt template wraps the "if (this != value)" in the setter with "if (iskey), so only primarykey fields receive this logic. Solution: it's not the most graceful thing, but I removed this check...we'll see how it pans out in real usage. I included the entire tt template, my changes are denoted with "**"... //////// //////// Write SimpleType Properties. //////// private void WriteSimpleTypeProperty(EdmProperty simpleProperty, CodeGenerationTools code) { MetadataTools ef = new MetadataTools(this); #> /// <summary> /// <#=SummaryComment(simpleProperty)#> /// </summary><#=LongDescriptionCommentElement(simpleProperty, 1)#> [EdmScalarPropertyAttribute(EntityKeyProperty= <#=code.CreateLiteral(ef.IsKey(simpleProperty))#>, IsNullable=<#=code.CreateLiteral(ef.IsNullable(simpleProperty))#>)] [DataMemberAttribute()] <#=code.SpaceAfter(NewModifier(simpleProperty))#><#=Accessibility.ForProperty(simpleProperty)#> <#=MultiSchemaEscape(simpleProperty.TypeUsage, code)#> <#=code.Escape(simpleProperty)#> { <#=code.SpaceAfter(Accessibility.ForGetter(simpleProperty))#>get { <#+ if (ef.ClrType(simpleProperty.TypeUsage) == typeof(byte[])) { #> return StructuralObject.GetValidValue(<#=code.FieldName(simpleProperty)#>); <#+ } else { #> return <#=code.FieldName(simpleProperty)#>; <#+ } #> } <#=code.SpaceAfter(Accessibility.ForSetter((simpleProperty)))#>set { <#+ **//if (ef.IsKey(simpleProperty)) **//{ if (ef.ClrType(simpleProperty.TypeUsage) == typeof(byte[])) { #> if (!StructuralObject.BinaryEquals(<#=code.FieldName(simpleProperty)#>, value)) <#+ } else { #> if (<#=code.FieldName(simpleProperty)#> != value) <#+ } #> { <#+ PushIndent(CodeRegion.GetIndent(1)); **//} #> <#=ChangingMethodName(simpleProperty)#>(value); ReportPropertyChanging("<#=simpleProperty.Name#>"); <#=code.FieldName(simpleProperty)#> = <#=CastToEnumType(simpleProperty.TypeUsage, code)#>StructuralObject.SetValidValue(<#=CastToUnderlyingType(simpleProperty.TypeUsage, code)#>value<#=OptionalNullableParameterForSetValidValue(simpleProperty, code)#>, "<#=simpleProperty.Name#>"); ReportPropertyChanged("<#=simpleProperty.Name#>"); <#=ChangedMethodName(simpleProperty)#>(); <#+ //if (ef.IsKey(simpleProperty)) //{ PopIndent(); #> } <#+ //} #> } }

  Read the article

• Can't get results from a IQueryable.

  - by StackPointer

  Hi! I have the following code in Linq to Entity: var policy= from pol in conn.Policy where pol.Product.DESCRIPTION=="someProduct" SELECT pol; Then, the table Policy, has some dependencies for a table called Entity. If I do this: foreach(Policy p in policy){ if(!p.Entity.IsLoaded) p.Entity.Load(); IEnumerable<Entity> entities= from ent in p.Entity Where ent.EntityType.DESCRIPTION=="SomeEntityType" select ent; Console.Writeline(entities.ElementAt(0).NAME); } It says, "Object not set to an instance", but if I do: foreach(Policy p in policy){ if(!p.Entity.IsLoaded) p.Entity.Load(); foreach(Entity et in p.Entity)Console.Write(et.NAME); } It works! Can anyone tell me why? Thank you, Best regards.

  Read the article

• ASP.net MVC DropLownList db.SaveChanges not saving selection

  - by WMIF

  I have looked through a ton of tutorials and suggestions on how to work with DropDownList in MVC. I was able to get most of it working, but the selected item is not saving into the database. I am using MVC 3 and Razor for the view. My DropDownList is getting created with the correct values and good looking HTML. When I set a breakpoint, I can see the correct selected item ID in the model getting sent to controller. When the view goes back to the index, the DropDownList value is not set. The other values save just fine. Here are the related views. The DropDownList is displaying a list of ColorModel names as text with the ID as the value. public class ItemModel { [Key] public int ItemID { get; set; } public string Name { get; set; } public string Description { get; set; } public virtual ColorModel Color { get; set; } } public class ItemEditViewModel { public int ItemID { get; set; } public string Name { get; set; } public string Description { get; set; } public int ColorID { get; set; } public IEnumerable<SelectListItem> Colors { get; set; } } public class ColorModel { [Key] public int ColorID { get; set; } public string Name { get; set; } public virtual IList<ItemModel> Items { get; set; } } Here are the controller actions. public ActionResult Edit(int id) { ItemModel itemmodel = db.Items.Find(id); ItemEditViewModel itemEditModel; itemEditModel = new ItemEditViewModel(); itemEditModel.ItemID = itemmodel.ItemID; if (itemmodel.Color != null) { itemEditModel.ColorID = itemmodel.Color.ColorID; } itemEditModel.Description = itemmodel.Description; itemEditModel.Name = itemmodel.Name; itemEditModel.Colors = db.Colors .ToList() .Select(x => new SelectListItem { Text = x.Name, Value = x.ColorID.ToString() }); return View(itemEditModel); } [HttpPost] public ActionResult Edit(ItemEditViewModel itemEditModel) { if (ModelState.IsValid) { ItemModel itemmodel; itemmodel = new ItemModel(); itemmodel.ItemID = itemEditModel.ItemID; itemmodel.Color = db.Colors.Find(itemEditModel.ColorID); itemmodel.Description = itemEditModel.Description; itemmodel.Name = itemEditModel.Name; db.Entry(itemmodel).State = EntityState.Modified; db.SaveChanges(); return RedirectToAction("Index"); } return View(itemEditModel); } The view has this for the DropDownList, and the others are just EditorFor(). @Html.DropDownListFor(model => model.ColorID, Model.Colors, "Select a Color") When I set the breakpoint on the db.Color.Find(...) line, I show this in the Locals window for itemmodel.Color: {System.Data.Entity.DynamicProxies.ColorModel_0EB80C07207CA5D88E1A745B3B1293D3142FE2E644A1A5202B90E5D2DAF7C2BB} When I expand that line, I can see the ColorID that I chose from the dropdown box, but it does not save into the database.

  Read the article

• Trouble with Code First DatabaseGenerated Composite Primary Key

  - by Nick Fleetwood

  This is a tad complicated, and please, I know all the arguments against natural PK's, so we don't need to have that discussion. using VS2012/MVC4/C#/CodeFirst So, the PK is based on the date and a corresponding digit together. So, a few rows created today would be like this: 20131019 1 20131019 2 And one created tomorrow: 20131020 1 This has to be automatically generated using C# or as a trigger or whatever. The user wouldn't input this. I did come up with a solution, but I'm having problems with it, and I'm a little stuck, hence the question. So, I have a model: public class MainOne { //[Key] //public int ID { get; set; } [Key][Column(Order=1)] [DatabaseGenerated(DatabaseGeneratedOption.None)] public string DocketDate { get; set; } [Key][Column(Order=2)] [DatabaseGenerated(DatabaseGeneratedOption.None)] public string DocketNumber { get; set; } [StringLength(3, ErrorMessage = "Corp Code must be three letters")] public string CorpCode { get; set; } [StringLength(4, ErrorMessage = "Corp Code must be four letters")] public string DocketStatus { get; set; } } After I finish the model, I create a new controller and views using VS2012 scaffolding. Then, what I'm doing is debugging to create the database, then adding the following instead of trigger after Code First creates the DB [I don't know if this is correct procedure]: CREATE TRIGGER AutoIncrement_Trigger ON [dbo].[MainOnes] instead OF INSERT AS BEGIN DECLARE @number INT SELECT @number=COUNT(*) FROM [dbo].[MainOnes] WHERE [DocketDate] = CONVERT(DATE, GETDATE()) INSERT INTO [dbo].[MainOnes] (DocketDate,DocketNumber,CorpCode,DocketStatus) SELECT (CONVERT(DATE, GETDATE ())),(@number+1),inserted.CorpCode,inserted.DocketStatus FROM inserted END And when I try to create a record, this is the error I'm getting: The changes to the database were committed successfully, but an error occurred while updating the object context. The ObjectContext might be in an inconsistent state. Inner exception message: The object state cannot be changed. This exception may result from one or more of the primary key properties being set to null. Non-Added objects cannot have null primary key values. See inner exception for details. Now, what's interesting to me, is that after I stop debugging and I start again, everything is perfect. The trigger fired perfectly, so the composite PK is unique and perfect, and the data in other columns is intact. My guess is that EF is confused by the fact that there is seemingly no value for the PK until AFTER an insert command is given. Also, appearing to back this theory, is that when I try to edit on of the rows, in debug, I get the following error: The number of primary key values passed must match number of primary key values defined on the entity. Same error occurs if I try to pull the 'Details' or 'Delete' function. Any solution or ideas on how to pull this off? I'm pretty open to anything, even creating a hidden int PK. But it would seem redundant. EDIT 21OCT13 [HttpPost] public ActionResult Create(MainOne mainone) { if (ModelState.IsValid) { var countId = db.MainOnes.Count(d => d.DocketDate == mainone.DocketNumber); //assuming that the date field already has a value mainone.DocketNumber = countId + 1; //Cannot implicitly convert type int to string db.MainOnes.Add(mainone); db.SaveChanges(); return RedirectToAction("Index"); } return View(mainone); } EDIT 21OCT2013 FINAL CODE SOLUTION For anyone like me, who is constantly searching for clear and complete solutions. if (ModelState.IsValid) { String udate = DateTime.UtcNow.ToString("yyyy-MM-dd"); mainone.DocketDate = udate; var ddate = db.MainOnes.Count(d => d.DocketDate == mainone.DocketDate); //assuming that the date field already has a value mainone.DocketNumber = ddate + 1; db.MainOnes.Add(mainone); db.SaveChanges(); return RedirectToAction("Index"); }

  Read the article

• Best datastructure for frequently queried list of objects

  - by panzerschreck

  Hello, I have a list of objects say, List. The Entity class has an equals method,on few attributes ( business rule ) to differentiate one Entity object from the other. The task that we usually carry out on this list is to remove all the duplicates something like this : List<Entity> noDuplicates = new ArrayList<Entity>(); for(Entity entity: lstEntities) { int indexOf = noDuplicates.indexOf(entity); if(indexOf >= 0 ) { noDuplicates.get(indexOf).merge(entity); } else { noDuplicates.add(entity); } } Now, the problem that I have been observing is that this part of the code, is slowing down considerably as soon as the list has objects more than 10000.I understand arraylist is doing a o(N) search. Is there a faster alternative, using HashMap is not an option, because the entity's uniqueness is built upon 4 of its attributes together, it would be tedious to put in the key itself into the map ? will sorted set help in faster querying ? Thanks

  Read the article

< Previous Page | 92 93 94 95 96 97 98 99 100 101 102 103  | Next Page >