ADO.NET :: Could Not Load An Entity When Table Is Existing
Oct 14, 2010
I always get this error when the table is existing in the database:
[Code]....
The inner exception of the error is this:
[Code]....
I checked the following for possible errors.
webconfig (both the values of the SQL connection string and the NHibernate connection string are the same)checked the existence of the tables.
Imagine that there are 4 records to be updated/inserted. The first 3 are successful. However, when the last record is to be inserted/updated, the error is thrown.
I got this error while inserting/updating a number of records
could not load an entity: [Star.CNPL_BusinessObjects.Entities.CNPL.CNPL_AgencyProduct#48][SQL: SELECT cnpl_agenc0_.Id as Id48_0_, cnpl_agenc0_.AgencyID as AgencyID48_0_, cnpl_agenc0_.ProductID as ProductID48_0_, cnpl_agenc0_.CreatedDate as CreatedD4_48_0_, cnpl_agenc0_.CreatedBy as CreatedBy48_0_, cnpl_agenc0_.UpdatedDate as UpdatedD6_48_0_, cnpl_agenc0_.UpdatedBy as UpdatedBy48_0_ FROM CNPL_AgencyProduct cnpl_agenc0_ WHERE cnpl_agenc0_.Id=?]" [code]...
How can I update an existing LINQ entity? This code gives me: "Cannot insert an entity that already exists." Any better practises on updating/inserting with linq?
foreach (ListViewItem lvi in lvStudents.Items) { HiddenField hfStudentID = lvi.FindControl("hfID") as HiddenField; CheckBox cbPresent = lvi.FindControl("mycb") as CheckBox; int sInt = Int32.Parse(hfStudentID.Value); dc = new DataClassesSODataContext();//I renewed the dc to make sure that wasn't the problem? var currStudent = dc.students.Single(x => x.studentID == sInt); grade g = dc.grades.Single(x => x.subjectID == subjID || x.studentID == sInt); if (g == null) { g = new grade(); g.subject = dc.subjects.Single(x => x.subjectID == subjID); g.student = currStudent; g.present = cbPresent.Checked; dc.grades.InsertOnSubmit(g); } else { g.present = cbPresent.Checked; dc.grades.Attach(g, true);//I tried both attaching and inserting } } dc.SubmitChanges();
I have an ASP.NET application with existing business classes and a database schema. (which I would like to keep) Currently I am using ADO.NET for the DAL, but I would like to switch to some advanced technology there for easier data retrieval.
Is EF applicable to my situation? Can I use it without splitting up my business classes and auto code generation? Can LINQ to SQL solve my problem better?
All I want to do is map my existing classes to the existing tables and dont have to handle details of the data retrieval myself.
I have an ASP.NET 4 web app that is using the Entity Framework to hold, amongst other things, a hierarchical structure of items that is used for features such as navigation.
One of the functions of the application allows the export of a particular branch of the hierarchy tree to XML, generated using a DataContractSerializer. Once exported, the intention is that the XML can then be uploaded to another instance of the same app, deserialized back into EF objects and then added to the data model on the second server.
When I try and import data in this way, I'm finding that I see the following error:
The object could not be added or attached because its EntityReference has an EntityKey property value that does not match the EntityKey for this object.
Taking a closer look at the XML that is generated by the serializer, I can see that the entity key is among the items that has been serialized. Since I'm importing entities that originate from a different database, some of the ID's clash.
What I'd ideally like to be able to do (unless I'm missing something here) is attach the imported entities to an object context and reset the ID's of the objects being imported.
Is there a smart way to do this? Do I simply have to set the ID for each of my imported entities to 0, attach them to the object context and then save changes?
I'm running into a really annoying problem with my Linq to SQL project. When I add everything in under the web project everything goes as expected and I can tell it to use my existing connection string stored in the web.config file and the Linq code pulls directly from the ConfigurationManager.
This all turns ugly once I move the code into its own project. I've created an app.config file, put the connection string in there as it was in the web.config but when I try to add another table in the IDE keeps forcing me to either hardcode the connection string or creates a Settings file and puts it in there, which then adds a new entry into the app.config file with a new name.
Is there a way keep my Linq code in its own project yet still refer back to my config file without the IDE continuously hardcoding the connection string or creating the Settings file? I'm converting part of my DAL over to use Linq to SQL so I'd like to use the existing connection string that our old code is using as well as keep the value in a common location, and one spot, instead of in a number of spots.
Manually changing the mode to WebSettings instead of AppSettings works untill I try to add a new table, then it goes back to hardcoding the value or recreating the Settings file. I also tried to switch the project type to be a web project and then rename my app.config to web.config and then everything works as I'd like it to. I'm just not sure if there are any downfalls to keeping this as a web project since it really isn't one. The project only contains the Linq to SQL code and an implementation of my repository classes.
My project layout looks like this
[code]....
Every time I try to make the default constructor look like the first way, it always auto changes back to the second way once I make a change to the file unless the DBML is inside of a web project.
I use a Detailsview, Entity Data Source to edit/update my table with only 3 columns.(it has primary keys).
Everything works fine inserts/edit in dev environment. but when i run this in release mode. i cannot update existing data in the database with the detailsview. whenever i update and save page gets refreshed, but nothing gets updated. but whenever i insert a new record, and then i try editing it. it works.?
Note: i handle DetailsviewItemUpdating,DetailsviewItemInserting events to do some custom checks.
I've tried deploying my asp.net app to a new server and I get this error:
Could not load file or assembly 'System.Web.Entity, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The system cannot find the file specified.
Sure enough, System.Web.Entity isn't found in C:WindowsAssembly. However, the server has MS .NET Framework 3.5 installed and also MS ASP.NET 2.0 AJAX Extensions 1.0. Is this something I need to deploy with my app, or something I need to be installed on the server? It's not my own server so xcopy deployment within my app folder would be much better if that's possible.
I developed and entity framework (.edmx) application in 4.0 in that i got all the data of my querying table and its foreign key referenced tables data also. but when i change my project to 3.5 i am unable to get the data of foreign key referenced tables data.
I have data entry form like...There are some empty rows and some of them have values. User can Update existing values and can also fill value in empty rows.I need to map these values in my DB table and some of them will be inserted as new rows into the database and existing record will be updated.I need your suggestions, How can I accomplish this scenario with best approach.
In an MVC view, I'm looking for a way to determine if a parent entity's collection of child entities is empty, so I can decide if I need to call a RenderPartial() or not.
For a one-to-one I've been using the following:
<% if (Model.Book.GenreReference.EntityKey != null) %> {.....}
but I'm unsure how to do it in a one-to-many scenario, or if it can even be done without the use of Include() or Load().
I am using GridView & EntityDataSource w/ eSQL SelectCommand. Assume i am using AdventureWorks Data model, how can i select more than one table? For example (eSQL),
[Code]....
But above code will make error , right now, i only can replace cat.*,sub.* to VALUE ROW(cat.CategoryID...[All Cat column] , sub.SubCategoryID.....[All SubCategory Column]) Which is very long command text.
I am working through the MVC Music Store example that is listed on this site. I am also trying to create my own MVC application in which I have several tables defined in a very similar way to the music store.
When I am defining my Models and running the application I am getting an error indicating that there is no key for a table that I know has a key. For example
Table1 int Id string fld1 int Table2_id
Table2 int Id string fldxyz
Code: public class Table1 { public int Id; public string fld1; public int Table2_id; public Table2 table2; }
public class Table2 { public int Id; public string Fldxyz }
of course the Id fields on the database are setup as being the key fields and are unique. When I run the application I am getting an error indicating the Table2 doesn't have a key and that it needs to be defined.
I am busy developing an application using EF4 and MVC2. My development database has a few extra fields that is not in my production database. I have removed the fields from the Model, and published my application to my web server. But now I am getting errors that says I have some invalid column names, but I have removed it from my model. If I go to my Mapping Details, I see the fields removed from the Model are still there, but not mapped to anything.
I have an html table with rows and cells. And I have dynamically created a label and would like to assign the label to one of the cells of the table. What I am doing is I have a JavaScript which executes a code behind method and it would not accept an already created asp.net label. So I have created the asp.net label programmatically but cant assign it to the table to display the text value of the label. Below is the code:
[System.Web.Services.WebMethod] public static void EndCandiateTest(){ try { totalTestMarks = ts.RetrieveResults(); grade = tsp.RawScoreAndGrade(totalTestMarks); remarks = tsp.ScoreInterpretation(totalTestMarks); testResults = "Raw Score: " + totalTestMarks.ToString() + " Grade: " + grade + " Remarks: " + remarks; ts.ShowResults(testResults); } catch (Exception e) { } } protected void ShowResults (string results). I want to display this label in an already existing html table. messageLabel.Text = results;
