Using a very run-of-the-mill database, with identity int for primary keys, a Dynamic Data Entities Project (EntityFramework) displays the primary key for view and edit. When using Linq to Sql, the primary key fields are not displayed.
I would like to hide the primary keys and use Entity Framework (VS 2008, .Net 3.5 sp1).
Due to the way the database was designed, in my model I have a User entity. The Contact entity inherits from the user entity, and the Profile entity inherits from the Contact entity.
How can I get a list of Profiles, and, how do I create a Profile?
Adding data into kartlar table (RehberID,KampanyaID,BrimID) is ok. But which Kart'ID created? I need to learn which Id created after adding data (RehberID,KampanyaID,BrimID) into Kartlar?
[code]...
How can I do that? I want to get data from Kartlar which data I added?
how to handle foreign keys with Entity Framework, when editing or adding a new record. For example, I have a person table, which has a timezone_id linking to my timezone table.
But the model seems to not include timezone_id. I see it's a new way of doing things, but ... how do I store my record?
My method:
[code]...
I can't do u.timezone_id = timezoneid;
I only have u.timezone (which seems to be the actual entity), and u.timezoneReference, which I am not sure what to do with.
I use the ObjectDataSource in an ASP.NET Application.
Using the ASPxGridView. When Updating it goes back to the Data Access Layer and tries to update the Entity, now as I can see while having some properites (Columns, Visible = false) when the entity arrives in the update method the visible = false columns have no values.
I don't want to show all the columns...what if I need 3 of the 30 columns? So I thought I would get the original entity from the context and merge the differences from the updated entity.
I have a Consumer class and a BillableConsumer : Consumer class. When trying to do any operation on my "Consumers" set, I get the error message "Object mapping could not be found for Type with identity Models.BillableConsumer.
From the CSDL:
[code]....
Is this because I did not specifically add the BillableConsumer entity to the object set? How do I do that in a POCO scenario?
i have following entities as you see BudgetPost has a composite primary key which is a foreign keys to entities Category and Budget. My question is what is the best way to make CRUD? Is there any way to mapp the foreign keys? The simple insert should look like this:
Budget newBudget = new Budget();
newBudget.BudgetName = textBox1.Text;
newBudget.FromDate = dateTimePicker1.Value;
newBudget.ToDate = dateTimePicker2.Value;
newBudget.BudgetPosts.Add(new BudgetPost { FKBudgetID = newBudget.BudgetID, FKCategoryID = 21, BudgetAmount = 700 });
db.AddToBudgets(newBudget);
db.SaveChanges();
let us assume that I have a reusable business layer that further makes use of a data access layer that was implemented using Entity Framework 4.0. The entities returned/consumed by the business layer are self-tracking, allowing us all the goodies that come with those type of entities. I would like to be able to store the entities I work with across post backs (on order to avoid re-querying every time). Basically let us assume I have a paged GridView with 10 items in it, and something like a DetailsView to edit those items. Every time you select a new row on the grid, the details view updates with the information of the selected row. My preference would be to only query for the entities on the initial request of the page and store it in session. Then subsequently I have a list of entities that I can work with and eventually modify and send back to the business layer with all of the changes.
I really want to use session instead of view state to reduce the page payload (self tracking entities are heavy) however I really like view state for this because of the fact that when the user navigates away from the page there is no residual effect. Some of the things that worry me are: When a user navigates away from the page to another page, the entities from the previous page are still in session. I could always do something on load of a page to do housekeeping type of work. Not sure if that's good practice. I am worried about people opening browser tabs and having two views into the same page, it seems like that might pose a problem. Is this even a good approach? Seems like I am trying to have the best of all worlds, it would definitely be much easier to simply re-query on every post back for the entities and pay the 50-100ms hit of the database trip.
I have a model that consists of Order, OrderLine, Product.
I want to create an Order and add OrderLines (each OrderLine related to a Product). I create the Order and add new OrderLines to it. Between posts I store the Order entity in Session (or ViewState). Just so you know I have added suppport for binary serialisation which works fine.
The relationship is therefore Order > OrderLine(s) > Product(s).
You might have already guessed what the problem is - that when I SaveChanges() I get the usual 'AcceptChanges cannot continue because the object's key values conflict with another object in the ObjectStateManager.' error.
I have referred to a number of articles online but none seem to handle this case (where I have the relationship across more than two entities) e.g. [URL].
This must be a very common requirement surely? Is there anyone out there doing the same kind of thing with Entity Framework (and without using DTOs etc)?
I am trying to get some guidance with this issue:
I have a Customer object that has two address ID fields (one for HomeAddress and one for WorkAddress)
I am loading the Address Objects by using Include="HomeAddress, WorkAddress" and then binding to the properties using the Navigation Property on the Customer Entity
Can I use just one FormView for doing the Insert/Updates and binding it to an EntityDataSource or would I have to do all the Inserting/Updating manually?
I have just added the Dynamic Data Filtering library to an Entity Framework based Dynamic Data web application, but on trying to access List.aspx, I get the following error. Is there anything I can do about this on .NET 4?The method 'Skip' is only supported for sorted input in LINQ to Entities. The method 'OrderBy' must be called before the method 'Skip'.
View 2 RepliesWe have a set of tables and views that merely store some config data for embedded devices. this schema is change-prone and do not really required lots of logic, beyond some validation rules. so we considered using a RAD tool for maintaining these CRUDS. In first stage: Dynamic Data But the community size, books absence and the last modification dates of the MSDN articles (~July 2008) makes me want to hear your experiences. (actually DynamicData comes as a part of the ASP.Net MVC2 project) What has been your experience with Dynamic Data? What is your favorite ASP.Net RAD alternative? Why?
View 1 RepliesI created two stored procedures in SQL Server Management Studio.
First procedure add field in ProjcetsToUsers table (for many-to-many associations)
[code]....
I can delete the user from the project and then add another, and the new one is added but removed the remains.
As for data base both this function work correctly.
I have an asp.net dynamic data website .net 3.5 built on ado.net entity framework with mysql database.Currently I have just one table in my entity model.
Everything is working fine on my local machine but when i uploaded on my server i got this error message:
"More than one item in the metadata collection match the identity 'mtDBModelStoreContainer'"
Note that this error happen when i open the table "WebsiteAdmin/users/List.aspx"
i have the following code where I want to retreive the data form a table using entity framework and put it to a list of the same type:
List<ItemDetail> iDets = new List<ItemDetail>();
iDets = (List<ItemDetail>) from l in db.ItemDetails
where l.ItemID == varItemID
select l;
when I run the page, it throws the following error:
Unable to cast object of type 'System.Data.Objects.ObjectQuery`1[LIBRIModel.ItemDetail]' to type 'System.Collections.Generic.List`1[LIBRIModel.ItemDetail]'.
why i'm having this problem? or am I missing something here if i'm not wrong it worked once, but now it throws this error
I've created a new ASP.NET website. I've generated an Entity Data Model from my database and have dropped a entitydatasource and gridview onto my page and wired up the gridview to pull from the entitydatasource. Now I get columns like this: id extension prefix did_flag len ten_id restriction_class_id sfc_id name_display building_id floor room phone_id department_id
In each case where the item is named something_id this reflects a foreign key relationship in the database - and I did choose to have the EDM expose foreign key relationships. I'd like to make it so the gridview pulls in the values for these foreign keys rather than just showing the ID numbers - so, for example, department_id might have a value of "101" right now but it should pull from the department table "Marketing".
Does ADO.Net Entity Framework 3.5 support Composite Foreign key/Composite primary key?
View 5 RepliesI'm working on a new project where I have the luxury of working from a Model to Database approach using Entity Framework 4.
The project I'm working on is taking an agile approach where different phases will be rolled out over time.
Will the Model First approach work in my case? I noticed when you "Generate Database from Model" it recreates the entire schema from scratch which will obviously wipe all the data that is in the db. I was hoping for a more "Update Database from Model" approach where the db would just be altered to reflect the changes rather than recreated
DbClick the code behind file of NerdDiner.edmx,It reads "This code was generated from a template." on the top comment lines. I generate my own .edmx file automatically with VS2010, just found that the .designer.cs file didnt contains Objectset,Methods as nerddinner does IDK which template hanselman used to generate this .edmx files，dont tell me he wrote it all by himself! Shoud .edmx and its code behind file be generated automaticlly without hard-coding?
View 4 RepliesIs there a way to export a EF 4.0 Data Model to EF 3.5?
I looked around and found that we are not able to access EF 4.0 from a ASP.Net 3.5 project here: [URL]
Our project is the 1st to go to .Net 4.0 using Entity Framework and we (the team) were wondering if there was a way for the other projects that "might" need to access our data that are still using the .Net 3.5 framework.
I have a textbox that takes an integer value, and a submit button that when clicked passes the value to a detailsview to display the database record at that index.
What I'd like to do is, when the button is clicked, compare the number to the keys in the detailsview's datasource so that if the record ID doesn't exist, I can display a label telling the user that the ID# doesn't exist.
How would I go about doing this? Is there some sort of compare method for the datakeynames property?
I have three table like above, table C is mapping table which has foreign key of Table A and B.How can i select and insert data in Table C using Entity Frame Work?
View 2 RepliesI am using .net framework 3.5 framework & for database operations entity framework. So, to fetch the data i am using LINQ queries & returns a resultset in a list.e.g
public class Emp
{
public int CD{get;set;}
[code]...
I am making a web project now. And i meet some problems working with Entity Framework. My program needs to have dynamic model. I try to explain. So i have classes and database is created from them. At the beginning of work program checks in folder Modules for assemblies and looks for classses that needs to be created as tables in database(this classes have to become a part of ef model). And i need at runtime create database.If some new classes was added so add this tables to database, but not recreate it(as it is made by default). If i delete classes the tables are not deleted.
View 2 RepliesIs it possible to choose a specific database that will be used with the entity framework? At this time, I use the connection string in the Web.Config as database authentication.
I have twelve databases, each of them has the same structure and the same stored procedure.
There is one database for each client. When a client wants to login into the system, he needs to choose his database name from a listbox.
I would like to create a dynamic connection string which will include the database name chosen by the client.