Is it possible to refresh only one entity in entity framework designer? Every time I refresh model from database, it refreshes all entities. The problem is that this mechanism doesn't recognize properly primary keys in views, so I have to correct it manually. Am I missing something?
No, you're not missing anything. When you update model using the GUI designer, the entire storage schema is regenerated. At least, that's how it works in Entity Framework 1.
I can't tell you if you can or can't do it, but I have one clue how to figure it out.
http://code.msdn.microsoft.com/EdmGen2
EdmGen2 contains source code and dll probably with functionalities from usual EdmGen.
Unfortunately I didn't have time to investigate this further. Hope this helps.
Related
I currently have an ASP.NET Core project using EF 3.1. I would like to use Code-First to manually build most of my entities, but there is also a linked server I need to incorporate data from as well. I need to figure out how to create an entity model that is the result of this view (that includes a left join from a code-first table I have already migrated). During my research thus far, it seems that since EF3 there is support for views inside of Scaffold-DbContext, but my concern is I would only want to scaffold this single view, but still access everything inside the same DbContext I am already using. I don't want to hack things together, so please let me know how you would accomplish such a task in your project. Thanks for your help!
Looks like I was able to figure this out after all. The steps I did are as follows, but please correct me if you know a better or more accepted way.
Selected the SQL view into a new table so I could generate a create script off of it.
Copied the create script into the class creation tool over at https://codverter.com/src/sqltoclass so didn't have to manually convert 20+ columns and types to class properties.
Copied the generated properties into a new model class named after the SQL view
Added a new DbQuery under my existing DbSets in my DbContext class. (It does seem like DBQuery is deprecated, but I don't see another way around using it currently) and named it the same as my SQL view.
Scaffolded a new controller off the SQL views model class and navigated to the generated index page to verify data could be seen. (it worked!)
Let me know if you have any better ideas on how I came to this solution!
I'm new to entity framework and database design and I'm using database first approach, which in visual studio 2012 default to creating POCO classes with DbContext API. I'm trying to keep the POCO classes as lean as possible and I encountered a scenario where I want to generate two types from a single table. My problem is I want to move the navigation properties along with the foreign keys to the derived types. Does anyone know a way to solve this problem?
NOTE: I tried to post an image of what I'm trying to do but apparently I still don't have enough reputation to do that.
Edit: Thanks to whomever gave me enough reputation to post an image. The image that I'm trying to post is below.
Thanks,
Raymond
Did you ever get a solution to this? I have a similar structure. I created a super-type table in my SQL Server DB with 2 sub-type, one has a relationship to another table. EF simply set it up for me. But you should be able to do it by right-clicking on your entity and adding a new navigation item. You can then create a new Association (also by right clicking).
Regards
I added new table to my database and I managed to add it to my data model, using "Update model from database" option. But I cant generate class to acces this table in code. "Add code generation item" results into creating classes for all tables i have in my database.
Well, it seems to be a duplicate, but don't delete this topic at once please, for I've been searching for solution quite a long time and found nothing helpful.
You don't need to add code generation item again if you already did it once. Normally it should be enough to save your EDMX file and generation should trigger. If it for any reason doesn't work, right click on .tt file responsible for generating your classes in the Solution Explorer and select Run Custom Tool from the context menu.
I am working on an iPhone app.
I have modified my data model in Core Data by adding an entity.
And now my app crashes.
I think that when doing that (changing the model) I have to remove some files and reset the data store so that things can work with my new model. But I just can't remember what exactly I need to do.
Thanks for any tip.
Answered this one just the other day! It's a common issue. You need to blow away your old database file first. Here's how to do it:
Adding new attributes in existing coredata model
Does anyone know what the esiest way to update the entity model after adding/deleting the fields in the database?
I am adding a few new fields to my database, then choose "Update Model from DB" and nothing happens. The model stays intact. Did anyone encounter the same problem?
Thanks for any feedback!
With EF that shipped for .net 3.5 I tend to follow the following steps:
Delete the connectionstring
Delete the model
Generate a new model
Build solution
This is perhaps not a very solid approach but it saves me time in the long run. In the future it is easier and more stable to do a refresh but I have gone from autogenerating my model to model-first.
I would definitely check out the EDM Generator which allows you to do a full generation of the model from scratch - Click here to go to the MSDN reference. It has saved me a lot of time and hope it will do the same for you.