Is it possible to refresh only one entity (which depends on one table) in entity framework 4.0 designer?
when I refresh model from sql server database, it refreshes all entities.
Thanks in advance.
No you can't refresh only one entity at a time with the update model from database wizard.
You can make a backup of your edmx, update it, open it as an xml file (right click>Open With>XML (Text) Editor), copy the modified sections about your entity (in the csdl, msl and ssdl sections), and paste them in your backup.
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I am using Entity Framework with a database-first approach, and I made some changes to the database. I cannot see those changes in my application because I know I need to update it too. But how do I update my domain models classes in ASP.NET MVC? Please can anyone help me?
Open your edmx file and Right click on your edmx diagram and select Update model from database
2.if you need to add/refresh the existing tables,select the tables under add/refresh button and finish
save the changes and build your solution
I'm currently working on an ASP.NET project which I've not done before, and I need to use Entity Framework to access a database. I have a database already and following along with this tutorial: https://msdn.microsoft.com/en-gb/data/jj200620
I've managed to get Entity Framework to create the classes for the tables in my database but it has created them all in my Views/Home directory like so:
But from my understanding of MVC these should go in the Models directory? Is it safe to just cut and paste these generated files into Models or am I going to run into problems in the future because it's going to still be trying to use View/Home?
It should be safe to move them to Models. The models are compiled, not deployed as website content, so ASP.NET does not care about their exact location.
You will probably want to update the namespaces of the models, though. I'm guessing that the models were created with a namespace like YourNamespace.Views.Home, and you will want to change it to YourNamespace.Models.
Also make sure to update the namespaces to any references to your models (if you have any). You will get compile errors for any references that you missed EXCEPT for any references in cshtml files.
It would be a lot easier to just delete everything created by EF, and add your ADO.NET Entity Data Model (.edmx file) again into the right folder.
On step 3 of the EF guide in your question, when you add the ADO.NET Entity Data Model, make sure you add it into the Models folder. (Right click on the Models folder, then Add New Item...)
I would like to generate EF POCO entities directly from my database using a connection string, but the templates that I can add to my project all expect me to have an .edmx file, which I do not. I can't seem to find out how to modify the template correctly to do this but I know it is possible. Any T4 template wizards out there that can help?
In the solution explorer, you can add an EDMX. Right-click, add, class, and select ADO.NET Entity Data Model. You can then select "EF Designer from database" and VS will generate the POCO entities for you. They'll be tucked inside the EDMX, nested under the .tt file.
From there, it's easy to manually create the metadata files as partial classes of the generated entities, however I've never generated the metadata properties automatically. https://msdn.microsoft.com/en-us/library/bb126445.aspx might get you there. If you find a better resource, let me know.
I've got an ASP.NET MVC 4 site with MSSQL database generated by code first approach. I want to use this database in another project. This project should crawl several tables from db, update them and send notification to users.
What is the best way to add existing database from the first project to the second project? I'm thinking about generating edmx by database, but this approach doesn't seem good enough.
You would be best moving the EF code and Entities into their own library, and then having your two different projects (Web and Windows Service) have a reference to that library.
Then, if and when your database structure or entities change, you only need to do this in one place.
If the second project is not going to modify the structure of the database, then I would use a data-first approach in your second project.
You can use codefirst mapping without problem on existing database. So simple reference assembly with datacontext in other project and it will work. (Don't forget set connection string in config file of other project)
I am working on an mvc app that uses some silverlight to supplement a page and instead of having to maintain two separate linq to sql classes I want to add a reference to the main project from the silverlight project but this can't be done through the normal method of just adding a reference, anyone have a workaround?
The normal way to do this is to create a new Silverlight class library project, and use "add as link" to add the existing files from your non-Silverlight project. You can then reference the new project in your main Silverlight project without duplicating any of the files.
Note that if you want to add the LINQ to SQL classes, just add the generated .designer.cs file to the new project--AFAIK dbml files themselves aren't supported in Silverlight projects. You will also need to stub out the L2S attributes present in the classes: ColumnAttribute, FunctionAttribute, and so on.
This may be more trouble than it's worth--if your goal is to communicate with the server using classes generated from a database, you might consider using the Entity Data Model with ADO.NET Data Services (the combination of which is intended for this purpose) instead of LINQ to SQL.