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  • LinqToSQL not updating database

    - by codegarten
    Hi. I created a database and dbml in visual studio 2010 using its wizards. Everything was working fine until i checked the tables data (also in visual studio server explorer) and none of my updates were there. using (var context = new CenasDataContext()) { context.Log = Console.Out; context.Cenas.InsertOnSubmit(new Cena() { id = 1}); context.SubmitChanges(); } This is the code i am using to update my database. At this point my database has one table with one field (PK) named ID. *INSERT INTO [dbo].Cenas VALUES (@p0) -- @p0: Input Int (Size = -1; Prec = 0; Scale = 0) [1] -- Context: SqlProvider(Sql2008) Model: AttributedMetaModel Build: 4.0.30319.1* This is LOG from the execution (printed the context log into the console). The problem i'm having is that these updates are not persistent in the database. I mean that when i query my database (visual studio server explorer - new query) i see the table is empty, every time. I am using a SQL Server database file (.mdf).

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  • How can i filter a list of objects using lamda expression?

    - by Colour Blend
    I know i shouldn't have id's with the same value. This is just fictitious, so overlook that. I have: List<Car> carList = new List<Car>(); carList.Add(new Car() { id = 1, name = "Honda" }); carList.Add(new Car() { id = 2, name = "Toyota" }); carList.Add(new Car() { id = 1, name = "Nissan" }); I want to use Lamda Expression to retreive all cars that have an id of 1. Anticipated Result: -- Id: 1, Name: Honda -- Id: 1, Name: Nissan The problem is more filtering an object list based on a foriegn key. Please help me.

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  • Expression.OrElse, dynamically creating a condition.

    - by Jim
    Hi, I am attempting to create a dynamic where clause using the standard expression API. var query = ( from p in Parties orderby p.PartyId orderby p.FullName select p ).AsQueryable(); Expression<Func<Party, bool>> @fn = (p) => SqlMethods.Like(p.FullName, "%smith%") || SqlMethods.Like(p.Person.FirstName, "%smith%"); Expression<Func<Party, bool>> @sn = (p) => SqlMethods.Like(p.Person.FirstName, words[0]); ParameterExpression pe = Expression.Parameter(typeof(Party), "p"); Expression orelse = Expression.OrElse( Expression.Lambda(@fn, pe), Expression.Lambda(@sn, pe) ); The expressions above will ultimately be added to a where clause. I need to add a bunch of 'likes'. How do I do this? I get InvalidOperationException on the operator OrElse I have also tried Expression.Or Thanks Regards Craig.

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  • xml attribure in dataset

    - by raging_boner
    I want to bind Repeater control to Dataset which is filled with XML data, but i don't know how to show attributes inside repeater. Xml File: <root> <items> <item id="9" name="111111111111" description="111111245" views="1" galleryID="0" /> </items> </root> Repeater code: <asp:Repeater ID="rptrGalleries" runat="server"> <ItemTemplate> <a href='Page?id=<%#DataBinder.Eval(Container.DataItem, "id") %>'><%#DataBinder.Eval(Container.DataItem, "name") %></a> </ItemTemplate> </asp:Repeater> Codebehind: XDocument doc = XDocument.Load(Server.MapPath("~/xml/gallery.xml")); IEnumerable<XElement> items = from item in doc.Descendants("item") orderby Convert.ToDateTime(item.Attribute("lastChanges").Value) descending where int.Parse(item.Attribute("galleryID").Value) == 0 && bool.Parse(item.Attribute("visible").Value) != false select item; DataSet ds = new DataSet(); ds.ReadXml(new StringReader(doc.ToString())); rptrGalleries.DataSource = ds; rptrGalleries.DataBind(); When I compile site I receive this error: System.Web.HttpException: DataBinding: 'System.Data.DataRowView' does not contain a property with the name 'id'.

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  • GridView will not update underlying data source

    - by John Christensen
    So I'm been pounding on this problem all day. I've got a LinqDataSource that points to my model and a GridView that consumes it. When I attempt to do an update on the GridView, it does not update the underlying data source. I thought it might have to do with the LinqDataSource, so I added a SqlDataSource and the same thing happens. The aspx is as follows (the code-behind page is empty): <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="Data Source=devsql32;Initial Catalog=Steam;Persist Security Info=True;" ProviderName="System.Data.SqlClient" SelectCommand="SELECT [LangID], [Code], [Name] FROM [Languages]" UpdateCommand="UPDATE [Languages] SET [Code]=@Code WHERE [LangID]=@LangId"> </asp:SqlDataSource> <asp:GridView ID="_languageGridView" runat="server" AllowPaging="True" AllowSorting="True" AutoGenerateColumns="False" DataKeyNames="LangId" DataSourceID="SqlDataSource1"> <Columns> <asp:CommandField ShowDeleteButton="True" ShowEditButton="True" /> <asp:BoundField DataField="LangId" HeaderText="Id" ReadOnly="True" /> <asp:BoundField DataField="Code" HeaderText="Code" /> <asp:BoundField DataField="Name" HeaderText="Name" /> </Columns> </asp:GridView> <asp:LinqDataSource ID="_languageDataSource" ContextTypeName="GeneseeSurvey.SteamDatabaseDataContext" runat="server" TableName="Languages" EnableInsert="True" EnableUpdate="true" EnableDelete="true"> </asp:LinqDataSource> What in the world am I missing here? This problem is driving me insane.

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  • Join two list comparing their elements properties

    - by 100r
    public class Person() { int ID; string Name; DateTime ChangeDate } var list1 = new List<Person> { new Person { ID= 1, Name = "Peter", ChangeDate= "2011-10-21" }, new Person { ID= 2, Name = "John", ChangeDate= "2011-10-22" }, new Person { ID= 3, Name = "Mike", ChangeDate= "2011-10-23" }, new Person { ID= 4, Name = "Dave", ChangeDate= "2011-10-24" } }; var list2 = new List<Person> { new Person { ID= 1, Name = "Pete", ChangeDate= "2011-10-21" }, new Person { ID= 2, Name = "Johny", ChangeDate= "2011-10-20" }, new Person { ID= 3, Name = "Mikey", ChangeDate= "2011-10-24" }, new Person { ID= 5, Name = "Larry", ChangeDate= "2011-10-27" } }; As output I would like to have list1 + list2 = Person { ID= 1, Name = "Peter", ChangeDate= "2011-10-21" }, Person { ID= 2, Name = "John", ChangeDate= "2011-10-22" }, Person { ID= 3, Name = "Mikey", ChangeDate= "2011-10-24" }, Person { ID= 4, Name = "Dave", ChangeDate= "2011-10-24" } Person { ID= 5, Name = "Larry", ChangeDate= "2011-10-27" } And the Algorithm is like this. Join two list. If elements of lists have same ID, compare them by ChangeDate and take the ond with bigger date. If ChangeDate are equeal take any of them but not both. Maybe its easier to concat both lists and than to filter them with lambda. I tried, but always came out with some ugly code :/ Anyone have any idea?

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  • LINQ2SQL DataLayer / Repository Suggestion

    - by MindlessProgrammer
    My current respository is as follows , please suggest , i am currently using LINQ2SQL Data context per insert/delele/update namespace Lib.Repository { public class MotorRenewalDataRepository { public MotorRenewalDataRepository() { } public MotorRenewalData GetByID(long id) { using(var _context=DatabaseFactory.Create(false)) { return _context.MotorRenewalDatas.Where(p => p.MotorRenewalDataID == id).FirstOrDefault(); } } public MotorRenewalData Insert(MotorRenewalData entity) { using (var _context = DatabaseFactory.Create(false)) { _context.MotorRenewalDatas.InsertOnSubmit(entity); _context.SubmitChanges(); return entity; } } public void Update(MotorRenewalData entity) { using (var _context = DatabaseFactory.Create(true)) { var dbEntity = _context.MotorRenewalDatas.Where(p => p.MotorRenewalDataID == entity.MotorRenewalDataID) .FirstOrDefault(); Common.CopyObject<MotorRenewalData>(entity, dbEntity); _context.SubmitChanges(); } } } }

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  • Is there an automatic way to generate a rollback script when inserting data with LINQ2SQL?

    - by Jedidja
    Let's assume we have a bunch of LINQ2SQL InsertOnSubmit statements against a given DataContext. If the SubmitChanges call is successful, is there any way to automatically generate a list of SQL commands (or even LINQ2SQL statements) that would automatically undo everything that was submitted? It's like executing a rollback even though everything worked as expected. Note: The destination database will either be Oracle or SQL Server, so if there is specific functionality for both databases that will achieve this, I'm happy to use that as well.

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  • Session is Closed! NHibernate shouldn't be trying to grab data

    - by Jeremy Holovacs
    I have a UnitOfWork/Service pattern where I populate my model using NHibernate before sending it to the view. For some reason I still get the YSOD, and I don't understand why the object collection is not already populated. My controller method looks like this: public ActionResult PendingRegistrations() { var model = new PendingRegistrationsModel(); using (var u = GetUnitOfWork()) { model.Registrations = u.UserRegistrations.GetRegistrationsPendingAdminApproval(); } return View(model); } The service/unit of work looks like this: public partial class NHUserRegistrationRepository : IUserRegistrationRepository { public IEnumerable<UserRegistration> GetRegistrationsPendingAdminApproval() { var r = from UserRegistration ur in _Session.Query<UserRegistration>() where ur.Status == AccountRegistrationStatus.PendingAdminReview select ur; NHibernateUtil.Initialize(r); return r; } } What am I doing wrong?

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  • Find Elements by Attribute using XDocument

    - by Ignacio
    This query seems to be valid, but I have 0 results. IEnumerable<XElement> users = (from el in XMLDoc.Elements("Users") where (string)el.Attribute("GUID") == userGUID.ToString() select el); My XML is as follows: <?xml version="1.0" encoding="utf-8" standalone="yes"?> <Users> <User GUID="68327fe2-d6f0-403b-a7b6-51860fbf0b2f"> <Key ID="F7000012ECEAD101"> ... </Key> </User> </Users> Do you have any clues to shed some light onto this?

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  • Given a Member Access lambda expression, convert it to a specific string representation with full ac

    - by Nathan
    Given an Expression<Func<T, object>> (e.g. x = x.Prop1.SubProp), I want to create a string "Prop1.SubProp" for as deep as necessary. In the case of a single access (e.g. x = x.Prop1), I can easily do this with: MemberExpression body = (expression.Body.NodeType == ExpressionType.Convert) ? (MemberExpression)((UnaryExpression)expression.Body).Operand : (MemberExpression)expression.Body; return body.Member.Name; However, if there is deeper nesting, e.g. x = x.Prop1.SubProp1, this only gets the most deeply nested name, e.g. "SubProp1" instead of "Prop1.SubProp1" Is there anyway to access the full property path of a lambda expression?

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  • How do I modify the contents of an XElement?

    - by voodoomsr
    is there a simple way to modify the InnerXml of a XElement? supose we have this extremely simple xml <planets> <earth></earth> <mercurio></mercurio> </planets> and we want to append some xml that come from another source that comes like a string "<continents><america/><europa/>.....blablabla" into the earth node. I read related questions but they talk about retrieving the innerxml of a XElement and i don't understand how "modify" the actual Xelement :(

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  • Testing a (big) collection retrieved from a db

    - by Bas
    I'm currently doing integration testing on a live database and I have the following sql statement: var date = DateTime.Parse("01-01-2010 20:30:00"); var result = datacontext.Repository<IObject>().Where(r => r.DateTime > date).First(); Assert.IsFalse(result.Finished); I need to test if the results retrieved from the statement, where the given date is less then the date of the object, have Finished set to False. I do not know how many results I get back and currently I'm getting the first object of the list and check if that object has Finished set to false. I know testing only the first item of the list is not valid testing, as a solution for that I could iterate through the list and check all items on Finished, but putting logic in a Test is kinda going against the concept of writing 'good' tests. So my question is: Does anyone have a good solution of how to properly test the results of this list?

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  • Using entity framework to detect changes in related table and action appropriate inserts and deletes

    - by Kohan
    Lets say i have a Person table, a Role table with a trel table PersonRoles linking them as many to many. I create a new person and assign them to 2 roles (role 1, role 3). I then want to edit this person; so i retrieve their data and bind their roles to a checkboxes. I change the values (Deselect role 1 and select role 2 instead) I then post this data back through a viewmodel. Can i then get Entity Framework to update these roles for me, as in delete the entry in PersonRoles to role 1 and then add a new entry as role 2? Or do i have to do the logic for this myself? Cheers, Kohan

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  • How to perform add/update of a model object that contains EntitySet

    - by David Liddle
    I have a similar concept to the SO questions/tags scenario however am trying to decide the best way of implementation. Tables Questions, QuestionTags and Tags Questions QuestionTags Tags --------- ------------ ---- QID QID TID QName TID TName When adding/updating a question I have 2 textboxes. The important part is a single textbox that allows users to enter in multiple Tags separated by spaces. I am using Linq2Sql so the Questions model has an EntitySet of QuestionTags with then link to Tags. My question is regarding the adding/updating of Questions (part 1), and also how to best show QuestionTags for a Question (part 2). Part 1 Before performing an add/update, my service layer needs to deal with 3 scenarios before passing to their respective repositories. Insert Tags that do not already exist Insert/Update Question Insert QuestionTags - when updating need to remove existing QuestionTags Here is my code below however started to get into a bit of a muddle. I've created extension methods on my repositories to get Tags WithNames etc. public void Add(Question q, string tags) { var tagList = tags.Split(new string[] { " " }, StringSplitOptions.RemoveEmptyEntries).ToList(); using (DB.TransactionScope ts = new DB.TransactionScope()) { var existingTags = TagsRepository.Get() .WithName(tagList) .ToList(); var newTags = (from t in tagList select new Tag { TName = t }).Except(existingTags, new TagsComparer()).ToList(); TagsRepository.Add(newTags); //need to insert QuestionTags QuestionsRepository.Add(q); ts.Complete(); } } Part 2 My second question is, when displaying a list of Questions how is it best to show their QuestionTags? For example, I have an Index view that shows a list of Questions in a table. One of the columns shows an image and when the user hovers over it shows the list of Tags. My current implementation is to create a custom ViewModel and show a List of QuestionIndexViewModel in the View. QuestionIndexViewModel { Question Question { get; set; } string Tags { get; set; } } However, this seems a bit clumsy and quite a few DB calls. public ViewResult Index() { var model= new List<QuestionIndexViewModel>(); //make a call to get a list of questions //foreach question make a call to get their QuestionTags, //to be able to get their Tag names and then join them //to form a single string. return View(model); } Also, just for test purposes using SQL Profiler, I decided to iterate through the QuestionTags entity set of a Question in my ViewModel however nothing was picked up in Profiler? What would be the reason for this?

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  • Should I return IEnumerable<T> or IQueryable<T> from my DAL?

    - by Gary '-'
    I know this could be opinion, but I'm looking for best practices. As I understand, IQueryable implements IEnumerable, so in my DAL, I currently have method signatures like the following: IEnumerable<Product> GetProducts(); IEnumerable<Product> GetProductsByCategory(int cateogoryId); Product GetProduct(int productId); Should I be using IQueryable here? What are the pros and cons of either approach? Note that I am planning on using the Repository pattern so I will have a class like so: public class ProductRepository { DBDataContext db = new DBDataContext(<!-- connection string -->); public IEnumerable<Product> GetProductsNew(int daysOld) { return db.GetProducts() .Where(p => p.AddedDateTime > DateTime.Now.AddDays(-daysOld )); } } Should I change my IEnumerable<T> to IQueryable<T>? What advantages/disadvantages are there to one or the other?

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  • I want to create a common unit test function to check all functions based on parameter

    - by Nilesh Rathod
    I want to create a common unit test function to check all functions based on parameter for e.g commonmethod(string methodname,string paramter1,....) { .... } what logic should i write inside this method so that by passing a actual function in parameter methodname and then the common method should execute that function and should return the output. i am using entity framework for all functions which has been created in my project and now i dont want to create a separate unit test function for each function.just one function should do the job based on different parameters... is that possible.. ?, if so then please provide me an code for same.. Thanks in advance..!!!

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  • Retrieve entities with children per one sql call. ADO.NET Entity framework

    - by Andrew Florko
    Hello everybody, I have two tables: A & B B { B1: Field1, B2: Field2, ... } A { Children: List of B, A1: Field1, A2: Field2, } I want to retrieve "A" entities with related "B" entities like this: DataContext.A.Select( a = new MySubset( A1 = a.A1, Children = a.Children.Select(b = b.B1).ToList()); But EF can't translate ToList into SQL, so i have to call ToList() per each instance in query producing additional network call. How can I avoid this? Thank you in advance.

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  • what is a performance way to 'tree-walking' through my Entity Framework data

    - by Greg
    Hi, I have a Entity Framework design with a few tables that define a "graph". So there can be a large chain of relationships between objects in the few tables via concept of parent/child relationships. What is a performance way to 'tree-walking' through my Entity Framework data? That is I assume I wouldn't want to load the full set of all NODES and RELATIONSHIPS from the database for the purpose of walking the tree, where the end result may only be identifying leaf nodes? Or would this be OK with the way lazy loading may work at the column/parameter level? Else how could I load just the skeleton of the objects and then when needing to refer to any attributes have them lazy load then?

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  • Does a TransactionScope that exists only to select data require a call to Complete()

    - by fordareh
    In order to select data from part of an application that isn't affected by dirty data, I create a TransactionScope that specifies a ReadUncommitted IsolationLevel as per the suggestion from Hanselman here. My question is, do I still need to execute the oTS.Complete() call at the end of the using block even if this transaction scope was not built for the purpose of bridging object dependencies across 2 databases during an Insert, Update, or Delete? Ex: List<string> oStrings = null; using (SomeDataContext oCtxt = new SomeDataContext (sConnStr)) using (TransactionScope oTS = new TransactionScope(TransactionScopeOption.Required, new TransactionOptions { IsolationLevel = System.Transactions.IsolationLevel.ReadUncommitted })) { oStrings = oCtxt.EStrings.ToList(); oTS.Complete(); }

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  • How to write sum calculation based on ria service?

    - by KentZhou
    When using ria service for SL app, I can issue following async call to get a group of entity list. LoadOperation<Person> ch = this.AMSContext.Load(this.AMSContext.GetPersonQuery().Where(a => a.PersonID == this.performer.PersonID)); But I want to get some calculation, for example, sum(Commission), sum(Salary), the result is not entity, just a scalar value. How can I do this?

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  • Formatting a query to enumerate through 2 different datatables

    - by boiler1974
    I have 2 datatables sendTable and recvTable They both have identical column names and numbers of columns "NODE" "DSP Name" "BUS" "IDENT" "STATION" "REF1" "REF2" "REF3" "REF4" "REF5" "REF6" "REF7" "REF8" I need to compare these 2 tables and separate out the mismatches I only need to check Columns 3-11 and Ignore col 1 and 2 I tried at first removing the 2 columns and then loop thru row by row and return matches and mismatches but the problem with this approach is that I no longer have the "NODE" and "DSP Name" associated with the row when I finalize my results So I need help with a query Here is my attempt var samerecordQuery = from r1 in sendTable.AsEnumerable() where r1.Field<int>("BUS").Equals(from r2 in recvTable.AsEnumerable() where r2.Field<int>("BUS")) this obviously doesn't work so how do I format the query to say from r1 cols[3-11] equals r2 cols [3-11] and once I have this I can use the except to pull out the mismatches

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