Entity Framework : How do you refresh the model when the db changes?
If you build the edmx file from the database and then the db changes, how do you get the开发者_Python百科 model to pick up the change?
Do you delete the whole model and regenerate or can you detect changes?
I see a post mentioning a "Update Your Model" rt. mouse command on the edmx file, but I dont see it.
Updating your edmx to reflect changes made in your db (.net linq-to-entities)
I'm just starting out.
Are you looking at the designer or code view? You can force the designer to open by right clicking on your EDMX file and selecting Open With -> ADO.NET Entity Data Model Designer
Right click on the designer surface of the EDMX designer and click Update Model From Database...
All entities are refreshed by default, new entities are only added if you select them.
EDIT: If it is not refreshing well.
- Select all the tables and view-s in the EDMX designer.
- Delete them.
- Then, update model from database
I have found the designer "update from database" can only handle small changes. If you have deleted tables, changed foreign keys or (gasp) changed the signature of a stored procedure with a function mapping, you will eventually get to such a messed up state you will have to either delete all the entities and "add from database" or simply delete the edmx resource and start over.
This might help you guys.(I've applied this to my Projects)
Here's the 3 easy steps.
- Go to your Solution Explorer. Look for .edmx file (Usually found on root level)
- Open that .edmx file, a Model Diagram window appears. Right click anywhere on that window and select "Update Model from Database". An Update Wizard window appears. Click Finish to update your model.
- Save that .edmx file.
That's it. It will sync/refresh your Model base on the changes on your database.
For detailed instructions. Please visit the link below.
EF Database First with ASP.NET MVC: Changing the Database and updating its model.
Update CodeFirst Model is not possible automatically. I don't recommend either. Because one of the benefits of code first is you can work with POCO classes. If you changed this POCO classes you don't want some auto generated code to destroy your work.
But you can create some template solution add your updated/added entity to the new model. then collect and move your new cs file to your working project. this way you will not have a conflict if it is a new entity you can simply adding related cs file to the existing project. if it is an update just add a new property from the file. If you just adding some couple of columns to one or two of your tables you can manually add them to your POCO class you don't need any extra works and that is the beauty of Working with Code-First and POCO classes.
Here:
- Delete the Tables from the EDMX designer
- Rebuild Project/SLN (this will clear the model class)
- Update Model from Database(readd all the tables you want)
- Rebuild project/SLN (this will recreate your model class including the new columns)
You need to be careful though, You need to setup the EDMX file exactly as it was before deleting it (if you choose the delete/regenerate route), otherwise, you'll have a naming mismatch between your code and the EF generated model (especialy for pluralization and singularization)
Hope this will prevent you some headaches =)
Double click on the .edmx file then right_click anywhere on the screen and choose "Update Modle From DB". In the new window go to the "Refresh" tab and choose the changed table/view and click Finish.
I just had to update an .edmx model. The model/Run Custom Tool option was not refreshing the fields for me, but once I had the graphical designer open, I was able to manually rename the fields.
I've been working on a project, not too large, that incorporates Entity Framework, about a dozen tables, and about 15 stored procs and functions. After weeks of development, attempting to refresh my tables and stored procs has yielded mixed results as far as successfully updating the model. Sometimes the changes are effective, most times they are not. Simple column changes (changing order, adding, removing, or renaming) sometimes works, most times does not. Visual Studio seems to have more problems with refreshing than just adding new. It also exhibits more problems with stored proc changes not being reflected, especially when columns are added or deleted or renamed. I have not detected any consistent behavior so i can't say "This type of change will always be updated and this type of change will not".
End result, if you want 100% effective solution, delete the EDMX file from the project, "Add new" item to project (ADO.NET Entity Data Model), and make sure you use the same name for the Model Name. This works every time.
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