I am trying to locate the Entity Data Model Wizard that allows you to populate the database schema into a DatabaseModel.edmx file so I can create my model based on that.
I've included the EntityFramework dlls into the project.json file but not too sure if in this new version of ASP.NET MVC this wizard is available anymore...
I've seen that the scaffolding that generates the Model classes is done through command line now but not sure if that has anything to do with the wizard I was talking about above.
Thanks!
"Prior to EF7 there are two ways to store models, in the xml-based EDMX file format or in code. Starting with EF7 we will be retiring the EDMX format and having a single code-based format for models."
Source: http://blogs.msdn.com/b/adonet/archive/2014/10/21/ef7-what-does-code-first-only-really-mean.aspx
Related
It is possible to use ASP.net EF Code first approach with Web Forms 4.5.2 ? I am currently using web forms to database first and would love to switch to code first approach.
Whether it is a console application or a complex engine project, the Data Access Layer can have any approach. So the direct answer is: yes you can.
You can generate code first classes and context from an existing database
All you need is to install Entity Framework 6.x (if not already done), then follow these instructions:
3.Reverse Engineer Model
Project > Add New Item…
Select Data from the left menu and then ADO.NET Entity Data Model.
Enter BloggingContext as the name and click OK.
This launches the Entity Data Model Wizard. Select Code First from Database and click Next.
Follow the wizard and it will generate the models and context with the connection
As stated in this tutorial, I can scaffold code-first EF Core from an existing database using Scaffold-DbContext in the Package Manager Console.
It's all good but my problem is that it scaffolds separate class files for each table and another for the context class. I find this a bit messy if I have too many tables.
I can rearrange it all by hand but Is there a way to scaffold everything to one class file? Or maybe having the context class on a separate file and then group the tables to another file per schema.
This behavior is not an option of EF Core scaffolding as of 1.0.0.
I get an error when I try publishing and going to my website. It says
You get this error when your c# code model is not in sync with your database tables.
Doing an EF migration will help to align those two things since EF will generate a set of SQL scripts to transform your database model to match up with your c# entities.
I've installed EntityFramework through nuget (should I do this for every project? Or can I just reference the assemblies? Where are they 'installed'? Sorry new to nuget)
I add a new "Ado.NET Entity Data Model" to my project and import tables from the database. However the context is added as ObjectContext not as the latest DbContext as I would presume. Am I missing something here?
Yes, install the package for each project. The assemblies are installed in a packages folder in the solution folder.
The ADO.NET Entity Data Model is for Database First. Read an explanation of Database First vs. Model First vs. Code First here:
http://www.asp.net/mvc/tutorials/getting-started-with-ef-using-mvc/creating-an-entity-framework-data-model-for-an-asp-net-mvc-application
A great place to start is http://asp.net. Read the tutorials. They cover data access with EF for both WebForms and MVC.
Can I generate entity framework model by clicking button in browser in client-side and save it back to web server PC?
EdmGen is the way to go if you're sure this is the best solution to your problem: http://msdn.microsoft.com/en-us/library/bb896270.aspx
If you're having problems with it could you please post the command line arguments you're using to call it?
You'll have to create a process in your web app (System.Diagnostics.Process) in order to kick off the executable from the browser side.
As David Neale says EmdGen is an option, if that is really what you want.
There is also EmdGen2, which has the advantage that it is able to work directly with the Edmx file:
EdmGen2 is a command-line tool for the
Microsoft ADO.NET Entity Framework.
The tool can be used as a replacement
for the EdmGen.exe tool that ships
with the .Net framework 3.5 SP1.
EdmGen.exe can only read and write the
CSDL, SSDL & MSL file formats.
However, EdmGen2.exe can read and
write the EDMX file format used by the
Visual Studio design tools.
Additionally, EdmGen2.exe can
translate between EDMX and CSDL, SSDL
& MSL formats, and the source code can
act as examples on using the tooling
APIs defined in the
System.Data.Entity.Design assembly.
Additionaly, EdmGen2.exe contains some
experimental functionality not found
in EdmGen.exe. Ankit Malpani, an
intern with Microsoft Research in
summer of 2008, and James Terwilliger,
a Post Doc researcher with MSR,
updated EdmGen2.exe with the ability
to identify inheritance
relatationships in relational database
schema. You can access this
functionality by using the
"RetrofitModel" option. The
RetrofitModel option connects to a
database instance and constructs an
EDM model (csdl, msl, ssdl, and edmx
files) that includes inheritance. The
tool uses data mining techniques to
identify TPT and TPH patterns in the
database instance, as well as vertical
partitioning, and constructs a
suitable model and mapping. To use the
tool, launch EdmGen2 with the
following arguments: