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  • Error using Dynamic Data Filtering: missing datasource

    - by sebastiaan
    I am trying to use the ASP.NET Dynamic Data Filtering project, but I'm running into a problem during the configuration. I'm following the instructions on the author's blog, and everything works like described. Then it tells me to change the datasource using the designer view. I am told to select the "GridDataSource" in the "Configure data source" wizard. This option is not there though. I get all of the classes in my project, including the DataContext that was generated by Linq. When I choose "Show only DataContext objects", the dropdown ("Choose your context object:") is completely empty. When I turn of the checkbox and choose my DataContext class, I get asked which table I want and all that. But, as the whole purpose of a Dynamic Data site is NOT to use one single table, that's not much help. So I've looked at the instructions again and copied the resulting datasource from the example: <asp:DynamicLinqDataSource ID="GridDataSource" runat="server" EnableDelete="True" EnableUpdate="True"></asp:DynamicLinqDataSource> Which is exactly what I had, without the "WhereParameters" nodes in there. Now, when I run the list page however, I get an exception about a missing datasource from the filtering component. Of course when I remove the DynamicFilterRepeater, it works again. This is the meat of the exception: [InvalidOperationException: Missing DataSource] Catalyst.Web.DynamicData.DynamicFilterRepeater.GetTable() in D:\Catalyst\Projects\DynamicData\Project\Trunk\DynamicData\DynamicData\DynamicFilterRepeater.cs:74 Catalyst.Web.DynamicData.DynamicFilterRepeater.GetFilters() in D:\Catalyst\Projects\DynamicData\Project\Trunk\DynamicData\DynamicData\DynamicFilterRepeater.cs:81 Catalyst.Web.DynamicData.DynamicFilterRepeater.OnInit(EventArgs e) in D:\Catalyst\Projects\DynamicData\Project\Trunk\DynamicData\DynamicData\DynamicFilterRepeater.cs:106 How do I make the DynamicFilterRepeater recognize my datasource? I'm using VS2010 Pro, on a Win7 machine.

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  • How to Process Lambda Expressions Passed as Argument Into Method - C# .NET 3.5

    - by Sunday Ironfoot
    My knowledge of Lambda expressions is a bit shaky, while I can write code that uses Lambda expressions (aka LINQ), I'm trying to write my own method that takes a few arguments that are of type Lambda Expression. Background: I'm trying to write a method that returns a Tree Collection of objects of type TreeItem from literally ANY other object type. I have the following so far: public class TreeItem { public string Id { get; set; } public string Text { get; set; } public TreeItem Parent { get; protected set; } public IList<TreeItem> Children { get { // Implementation that returns custom TreeItemCollection type } } public static IList<TreeItem> GetTreeFromObject<T>(IList<T> items, Expression<Func<T, string>> id, Expression<Func<T, string>> text, Expression<Func<T, IList<T>>> childProperty) where T : class { foreach (T item in items) { // Errrm!?? What do I do now? } return null; } } ...which can be called via... IList<TreeItem> treeItems = TreeItem.GetTreeFromObject<Category>( categories, c => c.Id, c => c.Name, c => c.ChildCategories); I could replace the Expressions with string values, and just use reflection, but I'm trying to avoid this as I want to make it strongly typed. My reasons for doing this is that I have a control that accepts a List of type TreeItem, whereas I have dozens of different types that are all in a tree like structure, and don't want to write seperate conversion methods for each type (trying to adhere to the DRY principle). Am I going about this the right way? Is there a better way of doing this perhaps?

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  • Subsonic 3, MySql, won't update record.

    - by Warspawn
    [WebMethod] public string GetAuthToken(string username, string password) { var db = new LogicDB(); //var results = from u in db.Users // where u.Username == username && u.Password == password // select u; User u = db.Select .From<User>() .Where(UsersTable.UsernameColumn).IsEqualTo(username) .And(UsersTable.PasswordColumn).IsEqualTo(password) .ExecuteSingle<User>(); if (u == null) { return "{'success': false, 'reason': 'Invalid username and/or password.'}"; } else { // really there should only be one match... Guid code = Guid.NewGuid(); u.Securitycode = code.ToString(); u.Securityexp = System.DateTime.Now.AddHours(24); //u.Save(db.Provider); return "{'id':'" + u.Id.ToString() + "', 'code':'" + code.ToString() + "', 'exp':'" + u.Securityexp.ToString() + "'}" + "\n\n<br/><br/>" + u.GetDirtyColumns().ToArray().ToString(); } } When I run that, I keep getting: System.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary. This is when u.Save(db.Provider); is uncommented. And happens even with just u.Save(); or using the linq query above results instead.

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  • Enabling Service Broker in SQL Server 2008

    - by Truegilly
    Hello, I am integrating SqlCacheDependency to use in my LinqToSQL datacontext. I am using an extension class for Linq querys found here - http://code.msdn.microsoft.com/linqtosqlcache I have wired up the code and when I open the page I get this exception - "The SQL Server Service Broker for the current database is not enabled, and as a result query notifications are not supported. Please enable the Service Broker for this database if you wish to use notifications." its coming from this event in the global.asax protected void Application_Start() { RegisterRoutes(RouteTable.Routes); //In Application Start Event System.Data.SqlClient.SqlDependency.Start(new dataContextDataContext().Connection.ConnectionString); } my question is... how do i enable Service Broker in my SQL server 2008 database? I have tried to run this query.. ALTER DATABASE tablename SET ENABLE_BROKER but it never ends and runs for ever, I have to manually stop it. once I have this set in SQL server 2008, will it filter down to my DataContext, or do I need to configure something there too ? thanks for any help Truegilly

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  • Use Session state within pLinq queries

    - by Dima
    Hi, I have a fairly simple Linq query (simplified code): dim x = From Product In lstProductList.AsParallel Order By Product.Price.GrossPrice Descending Select Product Product is a class. Product.Price is a child class and GrossPrice is one of its properties. In order to work out the price I need to use Session("exchange_rate"). So for each item in lstProductList there's a function that does the following: NetPrice=NetPrice * Session("exchange_rate") (and then GrossPrice returns NetPrice+VatAmount) No matter what I've tried I cannot access session state. I have tried HttpContext.Current - but that returns Nothing. I've tried Implements IRequiresSessionState on the class (which helps in a similar situation in generic http handlers [.ashx]) - no luck. I'm using simple InProc session state mode. Exchange rate has to be user specific. What can I do? I'm working with: web development, .Net 4, VB.net Step-by-step: page_load (in .aspx) dim objSearch as new SearchClass() dim output = objSearch.renderProductsFound() then in objSearch.renderProductsFound: lstProductList.Add(objProduct(1)) ... lstProductList.Add(objProduct(n)) dim x = From Product In lstProductList.AsParallel Order By Product.Price.GrossPrice Descending Select Product In Product.Price.GrossPrice Get : return me.NetPrice+me.VatAmount In Product.Price.NetPrice Get: return NetBasePrice*Session("exchange_rate") Again, simplified code, too much to paste in here. Works fine if I unwrap the query into For loops.

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  • LINQ2SQL - Binding result to a grid - want changes to be reflected without re-binding?

    - by Isaac
    Hello, I have a grid (DevExpress XtraGrid, if that matters) which is bound to a LINQ to SQL Entity property. gridItems.DataSource = purchaseOrder.PendingItemsGrouped; Well, the grid is being displayed properly,and I can see the purchase items that are pending. The problem arises when purchaseOrder.PendingItemsGrouped gets changed ... once that happens, the grid does not reflect the changes. The exact procedure is as following: The user selects a row from the grid, inserts a serial number on a specific textbox, and then hits enter effectively receiving this item from the purchase order, and inserting it into stock. inventoryWorker.AddItemToStock( userSelectedItem, serialNumber ); The item gets properly inserted to the inventory, but the grid still shows the item as if it is still awaiting it to be received. How do I solve this problem? Do I really need to re-bind the grid so the changes can be reflected? I even tried instead of: gridItems.DataSource = ...; This: gridItems.DataBindings.Add( new Binding( "DataSource", purchase, "PendingItemsGrouped" ) ); But couldn't solve the problem. Thank you very much for your time, Isaac. OBS: Re-Binding the Grid works, but my question is ... is that even the proper way of doing things? I feel like I'm miles off the right track.

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  • SubmitChanges doesn't save but removes inserts from change set, no errors

    - by winston schröder
    Hi Everybody, I have a deeper question regarding debug functionality of Linq to Sql SubmitChanges() Function. I want to save a record in a table of a locally cached db (localdbcache: server SqlExpress 2008 client SqlCE). Before calling SubmitChanges I can find the new item via DataContext.GetChangeSet(). After calling Submit Changes, the items to insert have been removed from the ChangeSet. (That's what this function is supposed to do.) There are no Changes Conflicts and no error in the db's log output. No Exception at all. The table's Count stays at the same value. if ((e.Parameter == null) || (!e.Parameter.GetType().Equals(typeof(LibDB.Client.Vehicles)))) return; LibDB.Client.Vehicles tmp = e.Parameter as LibDB.Client.Vehicles; try { ChangeSet cs = this._dc.GetChangeSet(); if ((tmp == null) || (this._dc == null)) return; if (this._dc.Vehicles.Where(veh => veh.Vin == tmp.Vin).Count() == 0) this._dc.Vehicles.InsertOnSubmit(tmp); else if (this._dc.Vehicles.Where(veh => veh.Vin == tmp.Vin).Count() == 1) this._dc.Vehicles.Attach(tmp, true); else return; using (TransactionScope ts = new TransactionScope()) { try { this._dc.SubmitChanges(); //this._dc.Refresh(RefreshMode.OverwriteCurrentValues, this._dc.Vehicles); } catch (Exception ex) { Console.WriteLine(ex.Message); } } if (this._dc.Vehicles.Where(veh => veh.Vin == tmp.Vin).Count() == 1) MessageBox.Show("Vehicle not saved."); this.vehSelector.ResetLayout(); } I would appreciate any help since I'm loosing hope to find any error, Thanks in Advance Winston

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  • Child objects in MongoDB

    - by Jeremy B.
    I have been following along with Rob Conery's Linq for MongoDB and have come across a question. In the example he shows how you can easily nest a child object. For my current experiment I have the following structure. class Content { ... Profile Profile { get; set; } } class Profile { ... } This works great when looking at content items. The dilemma I'm facing now is if I want to treat the Profile as an atomic object. As it stands, it appears as if I can not query the Profile object directly but that it comes packaged with Content results. If I want it to be inclusive, but also be able to query on just Profile I feel like my first instinct would be to make Profiles a top level object and then create a foreign key like structure under the Content class to tie the two together. To me it feels like I'm falling back on RDBMS practices and that feels like I'm most likely going against the spirit of Mongo. How would you treat an object you need to act upon independently yet also want as a child object of another object?

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  • Binding XML in Sliverlight without Nominal Classes

    - by AnthonyWJones
    Lets say I have a simple chunck of XML:- <root> <item forename="Fred" surname="Flintstone" /> <item forename="Barney" surname="Rubble" /> </root> Having fetched this XML in Silverlight I would like to bind it with xaml of this ilke:- <ListBox x:Name="ItemList" Style="{StaticResource Items}"> <ListBox.ItemTemplate> <DataTemplate> <StackPanel Orientation="Horizontal"> <TextBox Text="{Binding Forename}" /> <TextBox Text="{Binding Surname}" /> </StackPanel> </DataTemplate> </ListBox.ItemTemplate> </ListBox> Now I can bind simply enough with LINQ to XML and a nominal class:- public class Person { public string Forename {get; set;} public string Surname {get; set;} } So here is the question, can it be done without this class? IOW coupling between the Sliverlight code and the input XML is limited to the XAML only, other source code is agnostic to the set of attributes on the item element. Edit: The use of XSD is suggested but ultimately it amounts the same thing. XSD-Generated class. Edit: An anonymous class doesn't work, Silverlight can't bind them. Edit: This needs to be two way, the user needs to be able to edit the values and these value end up in the XML. (Changed original TextBlock to TextBox in sample above).

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  • How can I prevent 'objects you are adding to the designer use a different data connection...'?

    - by Timothy Khouri
    I am using Visual Studio 2010, and I have a LINQ-to-SQL DBML file that my colleagues and I are using for this project. We have a connection string in the web.config file that the DBML is using. However, when I drag a new table from my "Server Explorer" onto the DBML file... I get presented with a dialog that demands that do one of these two options: Allow visual studio to change the connection string to match the one in my solution explorer. Cancel the operation (meaning, I don't get my table). I don't really care too much about the debate as why the PMs/devs who made this tool didn't allow a third option - "Create the object anyway - don't worry, I'm a developer!" What I am thinking would be a good solution is if I can create a connection in the Server Explorer - WITHOUT A WIZARD. If I can just paste a connection string, that would be awesome! Because then the DBML designer won't freak out on me :O) If anyone knows the answer to this question, or how to do the above, please lemme know!

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  • Unit test with live data

    - by Kurresmack
    Hey, I have googled this a little and didn't really find the answer I needed. I am working on a webpage in C# with MSSQL and LINQ for a customer. I want the users to be able to send messages to each other. So what I do is that I unit test this with live data. The problem is that I now depend on having at least 2 users who I know the ID of. Furthermore I have to clean up after my self. This leads to rather large unit tests that test alot in one test. Lets say I would like to update a user. That would mean that I would have to ceate the user, update it, and then delete it. This a lot of assertions in one unit test and if it fails with updating i have to manually delete it. If I would do it any other way, without live data, I would not fore sure be able to know that the data was present in the database after updating etc. What is the proper way to do this without having a test that tests a lot of functuality by it self?

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  • ObjectDataSource.Select with Parameters Time Out

    - by MasterMax1313
    I'm using an ObjectDataSource with a 2008 ReportViewer control and Linq to CSV. The ODS has two parameters (the SQL is spelled out in an XSD file with a table adapter). The Reportviewer takes a very long time to render the output after a button is clicked to generate the report. That's my first problem. Even though it works (most of the time), the processing time worries me, and subsequent requests don't seem to be changing the results shown on the screen. The next issue is that when I go to export the ODS to CSV I'm getting a time out exception on the select method of the ODS (shown below). This works for ODS without parameters, but it seems like now that I've added parameters that it doesn't want to cooperate. I'm fresh out of ideas, any thoughts? <asp:ObjectDataSource ID="obsGetDataAllCustomers" runat="server" SelectMethod="GetDataAllCustomers" TypeName="my.myAdapter.AllCustomers" OldValuesParameterFormatString="original_{0}" > <SelectParameters> <asp:ControlParameter ControlID="StartDate" Name="Start" PropertyName="Text" Type="DateTime" /> <asp:ControlParameter ControlID="EndDate" Name="_End" PropertyName="Text" Type="DateTime" /> </SelectParameters> </asp:ObjectDataSource> After button click to view report - rvAllCustomers.LocalReport.Refresh() Export to CSV (adding the items returned to a list which is then processed by working code) - For Each dr As DataRow In CType(obs.Select(), DataView).Table.Rows l.Add(New FullOrderOutput(dr)) Next

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  • Unit test insert/update/delete

    - by Kurresmack
    Hey, I have googled this a little and didn't really find the answer I needed. I am working on a webpage in C# with MSSQL and LINQ for a customer. I want the users to be able to send messages to each other. So what I do is that I unit test this with data that actually goes into the database. The problem is that I now depend on having at least 2 users who I know the ID of. Furthermore I have to clean up after my self. This leads to rather large unit tests that test alot in one test. Lets say I would like to update a user. That would mean that I would have to ceate the user, update it, and then delete it. This a lot of assertions in one unit test and if it fails with updating i have to manually delete it. If I would do it any other way, without saving the data to DB, I would not for sure be able to know that the data was present in the database after updating etc. What is the proper way to do this without having a test that tests a lot of functuality in one test?

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  • Convert SQL with Inner AND Outer Join to L2S

    - by Refracted Paladin
    I need to convert the below Sproc to a Linq query. At the very bottom is what I have so far. For reference the fields behind the "splat"(not my sproc) are ImmunizationID int, HAReviewID int, ImmunizationMaintID int, ImmunizationOther varchar(50), ImmunizationDate smalldatetime, ImmunizationReasonID int The first two are PK and FK, respectively. The other two ints are linke to the Maint Table where there description is stored. That is what I am stuck on, the INNER JOIN AND the LEFT OUTER JOIN Thanks, SELECT tblHAReviewImmunizations.*, tblMaintItem.ItemDescription, tblMaintItem2.ItemDescription as Reason FROM dbo.tblHAReviewImmunizations INNER JOIN dbo.tblMaintItem ON dbo.tblHAReviewImmunizations.ImmunizationMaintID = dbo.tblMaintItem.ItemID LEFT OUTER JOIN dbo.tblMaintItem as tblMaintItem2 ON dbo.tblHAReviewImmunizations.ImmunizationReasonID = tblMaintItem2.ItemID WHERE HAReviewID = @haReviewID My attempt so far -- public static DataTable GetImmunizations(int haReviewID) { using (var context = McpDataContext.Create()) { var currentImmunizations = from haReviewImmunization in context.tblHAReviewImmunizations where haReviewImmunization.HAReviewID == haReviewID join maintItem in context.tblMaintItems on haReviewImmunization.ImmunizationReasonID equals maintItem.ItemID into g from maintItem in g.DefaultIfEmpty() let Immunization = GetImmunizationNameByID( haReviewImmunization.ImmunizationMaintID) select new { haReviewImmunization.ImmunizationDate, haReviewImmunization.ImmunizationOther, Immunization, Reason = maintItem == null ? " " : maintItem.ItemDescription }; return currentImmunizations.CopyLinqToDataTable(); } } private static string GetImmunizationNameByID(int? immunizationID) { using (var context = McpDataContext.Create()) { var domainName = from maintItem in context.tblMaintItems where maintItem.ItemID == immunizationID select maintItem.ItemDescription; return domainName.SingleOrDefault(); } }

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  • Can I stop the dbml designer from adding a connection string to the dbml file?

    - by drs9222
    We have a custom function AppSettings.GetConnectionString() which is always called to determine the connection string that should be used. How this function works is unimportant to the discussion. It suffices to say that it returns a connection string and I have to use it. I want my LINQ to SQL DataContext to use this so I removed all connection string informatin from the dbml file and created a partial class with a default constructor like this: public partial class SampleDataContext { public SampleDataContext() : base(AppSettings.GetConnectionString()) { } } This works fine until I use the designer to drag and drop a table into the diagram. The act of dragging a table into the diagram will do several unwanted things: A settings file will be created A app.config file will be created My dbml file will have the connection string embedded in it All of this is done before I even save the file! When I save the diagram the designer file is recreated and it will contain its own default constructor which uses the wrong connection string. Of course this means my DataContext now has two default constructors and I can't build anymore! I can undo all of these bad things but it is annoying. I have to manually remove the connection string and the new files after each change! Is there anyway I can stop the designer from making these changes without asking? EDIT The requirement to use the AppSettings.GetConnectionString() method was imposed on me rather late in the game. I used to use something very similar to what it generates for me. There are quite a few places that call the default constructor. I am aware that change them all to create the data context in another way (using a different constructor, static method, factory, ect..). That kind of change would only be slightly annoying since it would only have to be done once. However, I feel, that it is sidestepping the real issue. The dbml file and configuration files would still contain an incorrect, if unused, connection string which at best could confuse other developers.

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  • General SQL Server query performance

    - by Kiril
    Hey guys, This might be stupid, but databases are not my thing :) Imagine the following scenario. A user can create a post and other users can reply to his post, thus forming a thread. Everything goes in a single table called Posts. All the posts that form a thread are connected with each other through a generated key called ThreadID. This means that when user #1 creates a new post, a ThreadID is generated, and every reply that follows has a ThreadID pointing to the initial post (created by user #1). What I am trying to do is limit the number of replies to let's say 20 per thread. I'm wondering which of the approaches bellow is faster: 1 I add a new integer column (e.x. Counter) to Posts. After a user replies to the initial post, I update the initial post's Counter field. If it reaches 20 I lock the thread. 2 After a user replies to the initial post, I select all the posts that have the same ThreadID. If this collection has more than 20 items, I lock the thread. For further information: I am using SQL Server database and Linq-to-SQL entity model. I'd be glad if you tell me your opinions on the two approaches or share another, faster approach. Best Regards, Kiril

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  • Inner join on 2 arrays?

    - by russ
    I'm trying to find a solution to the following (I'm thinking with Linq) to the following: I need to pull down certain files from a larger list of files on an ftp server that have a similar file name. For example, we send an order file to some company for processing then they return a response file that we can download. So, I could send them the files "order_123.txt" and "order_456.txt". After a certain amount of time I need to go look for and download the responses for those files that will be named "order_123.resp" and "order_456.resp". The kicker is that in some cases I can have multiple responses in which case they would create "order_123-1.resp" and "order_123-2.resp" and also the files don't get removed from the server. I know this can be accomplished by looping through the files I know I need responses to then loop through all the files on the server until I find files that match but I'm hoping that I don't have to loop through the files on the server more than once. This example may help clarify: I've sent "order_222.txt" and "order_333.txt" they processed them and the ftp server contains: "order_111-1.resp" "order_001.resp" "order_222-1.resp" "order_222-2.resp" "order_333.resp" I need to download the 3rd, 4th, and 5th file. Thanks.

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  • Type or namespace could not be found

    - by Jason Shultz
    I'm using LINQ to SQL to connect my database to my home page. I created my datacontext (named businessModel.dbml) In it I have two tables named Category and Business. In home controller I reference the model and attempt to return to the view the table: var dataContext = new businessModelDataContext(); var business = from b in dataContext.Businesses select b; ViewData["WelcomeMessage"] = "Welcome to Jerome, Arizona!"; ViewData["MottoMessage"] = "Largest Ghost Town in America!"; return View(business); and in the view I have this: <%@ Import Namespace="WelcomeToJerome.Models" %> and <% foreach (business b in (IEnumerable)ViewData.Model) { %> <li><%= b.Title %></li> <% } %> Yet, in the view business is cursed with the red underline and say's that The type or namespace name 'business' could not be found (are you missing a using directive or an assembly reference?) What am I doing wrong? This has had me stumped all afternoon. link to all the code in pastebin: http://pastebin.com/es4RnS2q

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  • A many-to-many relation joined disallows intellisense/lookup in joined table

    - by BerggreenDK
    I want to be able to select a product and retrieve all sub-parts(products) within it. My approach is to find the Product id and then retrieve the list of ProductParts with that as a parent and while fetching those, follow the key back to the Product child to get the name and details of each Part. I was hoping to use something similar to: part.linked_product_id.name I have two tables. One for [Product] and and a relation [ProductPart] that has two FK ID's to [Product] Table Product() { int ID; // (PRIMARY, NOT NULL) String Name; ... details removed for overview purpose... } Table ProductPart() { int Product_ID; // FK (linked with relation to Product/parent) int Part_Product_ID; // FK (linked with relation to Product/childen) ... details removed for overview purpose... } I have checked the SQL-diagram and it shows the two relations (both are one to many) and in my DBML they also looks right. Here is my LINQ to SQL snippet that doesnt work for me... wondering why my joins dont work as supposed. FaultySnippet() { ProductDataContext db = new ProductDataContext(); var list = ( from part in db.ProductParts join prod in db.Products on part.Part_Product_ID equals prod.ID where (part.Product_ID == product_ID) select new { Name = part.Part_Product_ID. ?? // <-- NO details from Joined table? ... rest of properties from ProductPart join... I hoped... } ); }

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  • How to transform vertical table into horizontal table?

    - by avivo
    Hello, I have one table Person: Id Name 1 Person1 2 Person2 3 Person3 And I have its child table Profile: Id PersonId FieldName Value 1 1 Firstname Alex 2 1 Lastname Balmer 3 1 Email [email protected] 4 1 Phone +1 2 30004000 And I want to get data from these two tables in one row like this: Id Name Firstname Lastname Email Phone 1 Person1 Alex Balmer [email protected] +1 2 30004000 What is the most optimized query to get these vertical (key, value) values in one row like this? Now I have a problem that I done four joins of child table to parent table because I need to get these four fields. Some optimization is for sure possible. I would like to be able to modify this query in easy way when I add new field (key,value). What is the best way to do this? To create some StoreProcedure? I would like to have strongly types in my DB layer (C#) and using LINQ (when programming) so it means when I add some new Key, Value pair in Profile table I would like to do minimal modifications in DB and C# if possible. Actually I am trying to get some best practices in this case.

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  • Trying to generate all sequences of specified numbers up to a max sum

    - by Stecy
    Hi, Given the following list of descending unique numbers (3,2,1) I wish to generate all the sequences consisting of those numbers up to a maximum sum. Let's say that the sum should be below 10. Then the sequences I'm after are: 3 3 3 3 3 2 1 3 3 2 3 3 1 1 1 3 3 1 1 3 3 1 3 3 3 2 2 2 3 2 2 1 1 3 2 2 1 3 2 2 3 2 1 1 1 1 3 2 1 1 1 3 2 1 1 3 2 1 3 2 3 1 1 1 1 1 1 3 1 1 1 1 1 3 1 1 1 1 3 1 1 1 3 1 1 3 1 3 2 2 2 2 1 2 2 2 2 2 2 2 1 1 1 2 2 2 1 1 2 2 2 1 2 2 2 2 2 1 1 1 1 1 2 2 1 1 1 1 2 2 1 1 1 2 2 1 1 2 2 1 2 2 2 1 1 1 1 1 1 1 2 1 1 1 1 1 1 2 1 1 1 1 1 2 1 1 1 1 2 1 1 1 2 1 1 2 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I'm sure that there's a "standard" way to generate this. I thought of using linq but can't figure it out. Also, I am trying a stack based approach but I am still not successful. Any idea?

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  • Saving Abstract and Sub classes to database

    - by bretddog
    Hi, I have an abstract class "StrategyBase", and a set of sub classes, StrategyA/B/C etc. The sub classes use some of the properties of the base class, and have some individual properties. My question is how to save this to a database. I'm currently using SqlCE, and Linq-To-Sql by creating entity classes automatically with SqlMetal.exe. I've seen there are three solutions shown in this question, but I'm not able to see how these solutions will work or not with SqlMetal/entity classes. Though it seems to me the "concrete table inheritance" would probably work without any manual modifying. What about the other two, would they be problematic? For "Single Table Inheritance" wouldn't all classes get all variables, even though they don't need them? And for the "Class table inheritance" solution I can't really see at all how that will map into the entity-classes for a useful purpose. I may note that I extend these partial entity classes for making the classes of my business objects. I may also consider moving to EntityFramework instead of SqlMetal/Linq2Sql, so would be nice also to know if that makes any difference to what schema is easy to implement. One likely important thing to note is that I will constantly be develop new strategies, which makes me have to modify the program code, and probably the database shcema; when adding a new strategy. Sorry the question is a bit "all over the place", but hopefully it's some clear advantages/disadvantages here that you may be able to advice. ? Cheers!

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  • C# functional quicksort is failing

    - by Rubys
    I'm trying to implement quicksort in a functional style using C# using linq, and this code randomly works/doesn't work, and I can't figure out why. Important to mention: When I call this on an array or list, it works fine. But on an unknown-what-it-really-is IEnumerable, it goes insane (loses values or crashes, usually. sometimes works.) The code: public static IEnumerable<T> Quicksort<T>(this IEnumerable<T> source) where T : IComparable<T> { if (!source.Any()) yield break; var pivot = source.First(); var sortedQuery = source.Skip(1).Where(a => a.CompareTo(source.First()) <= 0).Quicksort() .Concat(new[] { pivot }) .Concat(source.Skip(1).Where(a => a.CompareTo(source.First()) > 0).Quicksort()); foreach (T key in sortedQuery) yield return key; } Can you find any faults here that would cause this to fail?

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  • Sorting out POCO, Repository Pattern, Unit of Work, and ORM

    - by CoffeeAddict
    I'm reading a crapload on all these subjects: POCO Repository Pattern Unit of work Using an ORM mapper ok I see the basic definitions of each in books, etc. but I can't visualize this all together. Meaning an example structure (DL, BL, PL). So what, you have your DL objects that contain your CRUD methods, then your BL objects which are "mapped" using an ORM back to your DL objects? What about DTOs...they're your DL objects right? I'm confused. Can anyone really explain all this together or send me example code? I'm just trying to put this together. I am determining whether to go LINQ to SQL or EF 4 (not sure about NHibrernate yet). Just not getting the concepts as in physical layers and code layers here and what each type of object contains (just properties for DTOs, and CRUDs for your core DL classes that match the table fields???). I just need some guidance here. I'm reading Fowler's books and starting to read Evans but just not all there yet.

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  • Utility of List<T>.Sort() versus List<T>.OrderBy() for a member of a custom container class

    - by ccomet
    I've found myself running back through some old 3.5 framework legacy code, and found some points where there are a whole bunch of lists and dictionaries that must be updated in a synchronized fashion. I've determined that I can make this process infinitely easier to both utilize and understand by converging these into custom container classes of new custom classes. There are some points, however, where I came to concerns with organizing the contents of these new container classes by a specific inner property. For example, sorting by the ID number property of one class. As the container classes are primarily based around a generic List object, my first instinct was to write the inner classes with IComparable, and write the CompareTo method that compares the properties. This way, I can just call items.Sort() when I want to invoke the sorting. However, I've been thinking instead about using items = items.OrderBy(Func) instead. This way it is more flexible if I need to sort by any other property. Readability is better as well, since the property used for sorting will be listed in-line with the sort call rather than having to look up the IComparable code. The overall implementation feels cleaner as a result. I don't care for premature or micro optimization, but I like consistency. I find it best to stick with one kind of implementation for as many cases as it is appropriate, and use different implementations where it is necessary. Is it worth it to convert my code to use the LINQ OrderBy instead of using List.Sort? Is it a better practice to stick with the IComparable implementation for these custom containers? Are there any significant mechanical advantages offered by either path that I should be weighing the decision on? Or is their end-functionality equivalent to the point that it just becomes coder's preference?

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