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System.Data.SQLite.EF6 Entities not found after modifying edmx diagram

I'm using EF6 with System.Data.SQLite 3rd party provider (there is no native support for SQLite in EF6).
I have to add inheritance between two tables. Because I can't do this on database level, I have to modify the .edmx diagram:
remove the original connection between the two tables (1:N connection), and replace it with the inharitance
rename one of the two tables, because EF automatically generates the name, which is not fit to our naming conventions
After I do this Visual Studio won't see the tables (none of them, nor the tables I have not modified), and I get several errors after build ("The type or namespace '' could not be found." ). Also, all of my table.cs files get removed from under ApplicationDatabase.tt.
If I undo the changes (revert back to the 1:N connection), and save the diagram and the database model everything works fine again.
What am I missing during the changes?

Ok, I solved it by removing the Id from the inherited table. I think the problem was that both tables had an Id, and it conflicted somehow because of the inheritance. Now everything just works fine.

Same table names, different schema issue in EDMX (Database first)

I have two tables with Same table name and different schema in the same database.
For example - Vendor.Employee and Customer.Employee
I am now adding EDMX file in my Class Library project under VS 2012. I am using EntityFramework 5.0.
Though it creates edmx files successfully without any issues, but it creates these entities with different names (like, Vendor.Employee is created as Employee entity, whereas Customer.Employee is created as Employee1 entity.
I understand its because both the classes are directly under same namespace, and so they get created with same names.
But is there any way (for example, giving namespaces per schema) or alternate to resolve this issue so we can have same table names.
Any help on this much appreciated.
Thanks and Regards

EF 5.x DbContext Generator - Namespace Issues

I'm trying to update a project to work in ASP.NET MVC4 using EF5(Database First approach as there is an existing db). I'm doing this with VS2010.
I am following the steps in this example.
These are the steps that I'm taking:
Set up a new MVC4 project simply called Project.NET
Create the Entity Data Model as ProjectModel.edmx
The connection string is saved as ProjectEntities
The model namespace is set to ProjectModel
Add an EF 5.x DbContext Generator item called ProjectModel.tt
So after all that, it has created the classes to be used by EF; the problem is that these classes are all created with the project's root namespace, rather than the namespace I have provided it.
If I open up any of the generated classes, I get a list of errors that are fixed by manually changing the namespace to ProjectModel
I'd appreciate any thoughts.
Update:
This is a screenshot showing the project structure, an example of the generated code, and the compiler errors.
What's odd is that it only seems to throw an error for a namespace based on the structure, so in the image Project.Models as the namespace creates an issue, but if I type in anything else such as ProjectModels or Test the errors disappear. I can change the the namespace on all the files, sure, but every time the model changes and is updated, the namespace will be reset and the errors return.
This question seems to be the same issue as the one I am having, but unfortuntely, the only answer given advised checking references; I believe mine are fine as System.Data.Entity and EntityFramework are present.
Update 2:
If I don't select all tables to during the code generation no namespace issues appear. I'm currently updating the model in 20 table intervals, with 400 tables though, I'd rather figure out what the actual issue is. I'm assuming it is due to the structure or name of one or more tables, but I'm not sure on whether or not there are any specific rules with regard table structure or naming with regard to EF.

Looks like your project is targeting .NET 2.0. Right-click on your project and choose Properties. make sure Target framework is set to .NET 4 or later.

It appears as though one of the tables which is called System was conflicting with the .NET System namespace. I guess I'll just have to change the table name to something else.

If you are adverse to making changes to your data schema, you can configure Entity Framework to map the table name to a different type/class. Something like this may help.

I achieved to set a custom namespace for the generated classes by setting the Custom Tool Namespace field in the .edmx model properties, and also in the properties of both the .tt files under it, using the Properties window.

Entity Framework conflict with same table name from different databases

I am using Entity Framework 4 with MVC 3 in Visual Studio 2012 (C#).
I am using database first; there are two separate databases each with its own namespace and with two separate edmx files. Each database has a table with the same name and fields (but different content). When I added the second table I started to get compile errors.
Ambiguity between 'Interface.CodeFormStatus.FormStatusCodeID'
and 'Interface.CodeFormStatus.FormStatusCodeID'
There seem to be some complex workarounds or I could rename one of the tables. Is there not a straightforward solution as this must be a fairly common issue.

I ran into a situation where I had two databases (one an older version of the other) and I needed to integrate both into a single project. Naturally, almost every name conflicted.
I created two separated edmx files for each database, and put each in its own namespace for clarity. I then edited each entity name to reflect which database it was coming from - (e.g. "Activities", which was in both, became "v13Activities" and "v14Activities").
For operations which were to be mirrored between both databases, I wrote a wrapper that included both contexts. This made my code was much less repetitive, and it had less synchronization issues.
Hope this approach helps someone else - it seems like this is an obscure question, and this answer was one of the top results on Google!
Update: In EF 6.1+, there is another solution. You can have "conflicting" names, and separate them with simple namespacing when using the "Code First From Database" option. I would advocate for this solution going forward, as the old XML .edmx style is going to be phased out starting in EF Core.

This worked for me. Just click on the table in the designer (the graphical version not the code) Then in the properties next to the, "Name" attribute you can change the name to something different. This will just change the name within the designer and used more as an alias throughout the application.

If you don't have many tables with the same name, then you could edit entity name in designer (your .edmx file).
So, just double-click a name of one of your CodeFormStatus entities and make it different (for example, change it to CodeFormStatusOther)

Change entities and properties names in Database First

I'm starting a new application that must use an existing database that use some naming conventions that are really annoying in .net (table names start with several trigrams that specify the business domain of the table, column names start with the tables trigram, trigrams are in uppercase and separated by underscores, etc.,).
What I'd like to do is to write a simple renaming rule (this is as simple as finding the last underscore and take everything after that) and apply it in Entity Framework. I don't really want to edit the names one by one in the editor, especially because the database might change and I don't want to do it several times.
I'm using Database First (as the database already exists and it is "the master"), and EF 4.x DbContext Generator and it works really great out of the box (with badly named classes and properties though).
I edited the T4 templates in order to rename the generated entities and properties, but when I try to perform any request, the DbContext object can't find the table that matches with the entity I'm trying to request and I get this exception :
The entity type [Entity Name] is not part of the model for the
current context.
This is obvious why it doesn't find the table : nothing tells it how to match the entity name and the table as I changed it on the fly.
I read that I can add instructions in the OnModelCreating(DbModelBuilder modelBuilder) method but this is not used in Database First (and the default T4 template adds an exception in it, just in case).
So now I'm stuck, I don't know how to specify that matching.
Here are several ideas I have but not sure if it's correct or doable :
Using the "plural / singular" API to change the name of the Entity ? Sounds like a dirty workaround. But it might work (didn't try though).
Finding a way to edit the EDMX file on the fly.
Editing the EDMX afterwards but it might complicate the process (edit in the designer, then execute a tool to alter the EDMX, then run custom tool to regenerate entities and DbContext... while today I just have to edit in the designer).
Using Code First (as it seems easier to use different entity names than table names, through attributes or instructions in the DbContext class), but it sounds like it would not be more complicated to use it with an existing database.
Any idea ? Or did I miss something ?

You won't be able to use a T4 transform for this, as you want to change the content of the actual .edmx file to map your store entity names (with the obnoxious prefixes) to your sanitized conceptual entity names.
Instead, you're better off writing an application that takes an .edmx file as input and sanitizes the names under the conceptual model tag and modifies the mapping names to reflect the sanitized names. I understand that this is your third option and that you wanted to avoid this if possible, but this is the most straightforward way to go about it. Bear in mind that you'll only have to run this tool when you add new tables or columns.