Looking for a method to automatically create entity classes from existing Postgres 13 database.
in
According to
http://www.npgsql.org/efcore/index.html
In Visual Studio 2019 command prompt
dotnet ef dbcontext scaffold "Host=my_host;Database=my_db;Username=my_user;Password=my_pw" Npgsql.EntityFrameworkCore.PostgreSQL
Command should do this but it throws error
Could not execute because the specified command or file was not found.
Possible reasons for this include:
* You misspelled a built-in dotnet command.
* You intended to execute a .NET program, but dotnet-ef does not exist.
* You intended to run a global tool, but a dotnet-prefixed executable with this name could not be found on the PATH.
NpgSql.EntityFrameworkCore.PostgreSQL v5.0.1 package is installed from Nuget.
You should install Dotnet EF tool.
try this in your package manager console
dotnet tool install --global dotnet-ef
After that it is recommended to install design tool aswell so you can use tools on specific project
dotnet add package Microsoft.EntityFrameworkCore.Design
Are they only needed at design time? Can they be removed without causing any build issues? (Targeting framework netcoreapp2.1).
The package of Microsoft.AspNetCore.Razor.Design contains MSBuild support for Razor. If you're developing an asp.net core app, there's no need to add an package reference on Microsoft.AspNetCore.Razor.Design manually (and also you're not supposed to remove them manually). Because it is referenced by Microsoft.AspNetCore.App meta package, which means if you have a dependency on Microsoft.AspNetCore.App, you'll reference the package automatically.
The package of Microsoft.VisualStudio.Web.CodeGeneration.Design is a quite different one. As the name suggests, it is used to generate codes only. For example, you want to develop a project without Visual Studio:
You create a new project using the command of dotnet new mvc
And then you create a new Model named App.Models.MyModel mannually
Typically, we'll use Visual Studio to generate controllers, views, DbContext and so on. But what if we don't have Visual Studio?
If we have the Microsoft.VisualStudio.Web.CodeGeneration.Design referenced in our *.csproj file, we can create the CRUD scaffold using the following command :
dotnet aspnet-codegenerator controller -m $model -dc $dcClass -name $controllerName -namespace $controllerNamespace -outDir Controllers --useDefaultLayout
There're also some other sub commands such as :
dotnet aspnet-codegenerator identity -dc $dcClass
However, this package is only used to scaffold. Once you have the codes generated, you can feel free to remove this package before publish.
As a side note, to use the dotnet aspnet-codegenerator command, we should first install the tool:
dotnet tool install --global dotnet-aspnet-codegenerator
I am new to EF core and I'm trying to get it to work with my ASP.NET Core project.
I get the above error in my startup.cs when trying configure the DbContext to use a connection string from config. I am following this tutorial.
The problematic code is in startup.cs:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.SpaServices.Webpack;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.EntityFrameworkCore;
using tracV2.models;
using tracV2.data;
namespace tracV2
{
public class Startup
{
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
// Add framework services.
services.AddMvc();
services.AddSingleton<IConfiguration>(Configuration);
string conn = Configuration.GetConnectionString("optimumDB");
services.AddDbContext<tracContext>(options => options.usesqlserver(conn));
}
The UseSqlServer method is recognized if I put it directly into the context:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
namespace tracV2.data
{
public class tracContext : DbContext
{
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
optionsBuilder.UseSqlServer("myrealconnectionstring");
}
All my research online points to missing references, but I can't seem to find out which one I am missing (see image).
First we install the Microsoft.EntityFrameworkCore.SqlServer NuGet Package:
PM > Install-Package Microsoft.EntityFrameworkCore.SqlServer
Then, after importing the namespace with
using Microsoft.EntityFrameworkCore;
we add the database context:
services.AddDbContext<AspDbContext>(options =>
options.UseSqlServer(config.GetConnectionString("optimumDB")));
adding
using Microsoft.EntityFrameworkCore;
manually solved the problem for me
Found that here
Edit...
for dotnet core 3.1 add
Microsoft.EntityFrameworkCore.SqlServer
Follow the steps below.
Install Entity Framework Core Design and SQL Server database provider for Entity Framework Core:
dotnet add package Microsoft.EntityFrameworkCore.Design
dotnet add package Microsoft.EntityFrameworkCore.SqlServer
Import Entity Framework Core:
using Microsoft.EntityFrameworkCore;
And configure your DbContext:
var connectionString = Configuration.GetConnectionString("myDb");
services.AddDbContext<MyDbContext>(options =>
options.UseSqlServer(connectionString)
);
Install below NuGet Package will solve your issue
Microsoft.EntityFrameworkCore.SqlServer
Install-Package Microsoft.EntityFrameworkCore.SqlServer
EntityFramework UseSqlServer Solved
Install-Package Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore
Install-Package Microsoft.EntityFrameworkCore.SqlServer
I believe this can be solved by adding a project reference to Microsoft.EntityFrameworkCore.SqlServer.Design
Install-Package Microsoft.EntityFrameworkCore.SqlServer.Design
Microsoft.EntityFrameworkCore.SqlServer wasn't directly installed in my project, but the .Design package will install it anyway as a prerequisite.
The Package is missing. Open Package Manager Console and execute the code below:
Install-Package Microsoft.EntityFrameworkCore.SqlServer
your solution works great.
When I saw this video till 17 Minute: https://www.youtube.com/watch?v=fom80TujpYQ
I was facing a problem here:
services.AddDbContext<PaymentDetailContext>(options =>
options.UseSqlServer(Configuration.GetConnectionString("DevConnection")));
UseSqlServer not recognizes so I did this
Install-Package Microsoft.EntityFrameworkCore.SqlServer -Version 3.1.5
&
using Microsoft.EntityFrameworkCore;
Then my problem is solved. About me: basically I am a purely PHP programmer since beginning and today only I started .net coding, thanks for good community in .net
Install the following packages from Nuget :-
Microsoft.EntityFrameworkCore
Microsoft.EntityFrameworkCore.Sqlite.Core
I was using Visual Studio Code.
1) Try to install the package 'Microsoft.EntityFrameworkCore.SqlServer' by specifying the version number.
VS Code:
'dotnet add package Microsoft.EntityFrameworkCore.SqlServer -v 1.1.1'
Visual Studio:-
'Install-Package Microsoft.EntityFrameworkCore.SqlServer -v 1.1.1'
Refer the link 'Package 'Microsoft.EntityFrameworkCore.SqlServer' is incompatible with 'all' frameworks in the project' for doing it.
2) Then add the namespace 'using Microsoft.EntityFrameworkCore;' manually in the Startup.cs file.
Refer the below link
https://github.com/aspnet/EntityFramework/issues/7891.
3) If you get any dependency issue for 'Microsoft.EntityFrameworkCore.SqlServer.Design', like "Package 'Microsoft.EntityFrameworkCore.Design' is incompatible with 'all' frameworks in project" ,we need to run the below command,
VS Code:-
dotnet add package Microsoft.EntityFrameworkCore.Design -v 1.1
Visual Studio
Install-Package Microsoft.EntityFrameworkCore.Design -v 1.1
Project -> ManageNugetPackages -> Browse -> Search "Microsoft.EntityFrameworkCore.SqlServer" and install or update.
As mentioned by top scoring answer by Win you may need to install Microsoft.EntityFrameworkCore.SqlServer NuGet Package, but please note that this question is using asp.net core mvc. In the latest ASP.NET Core 2.1, MS have included what is called a metapackage called Microsoft.AspNetCore.App
https://learn.microsoft.com/en-us/aspnet/core/fundamentals/metapackage-app?view=aspnetcore-2.2
You can see the reference to it if you right-click the ASP.NET Core MVC project in the solution explorer and select Edit Project File
You should see this metapackage if ASP.NET core webapps the using statement
<PackageReference Include="Microsoft.AspNetCore.App" />
Microsoft.EntityFrameworkCore.SqlServer is included in this metapackage. So in your Startup.cs you may only need to add:
using Microsoft.EntityFrameworkCore;
In Visual Studio, check the NuGet Package Manager => Manage Packages for Solution, check all this packages, whether got installed in your solution or not, as below:
EntityFrameworkCore
Microsoft.EntityFrameworkCore
Microsoft.EntityFrameworkCore.InMemory
Microsoft.EntityFrameworkCore.Relational
Microsoft.EntityFrameworkCore.Sqlite.Core
Microsoft.EntityFrameworkCore.SqlServer
Microsoft.EntityFrameworkCore.Tools
I solved the same issues after check all the above packages have been installed.
Install package, EntityFrameworkCore.SqlServer:
PM> Install-Package Microsoft.EntityFrameworkCore.SqlServer -Version 3.1.3
Nuget:
https://www.nuget.org/packages/Microsoft.EntityFrameworkCore.SqlServer/
I also had the same problem. I added the following. It works for me
Microsoft.EntityFrameworkCore.SqlServer
In my case :-
I have hit the below command and it is resolved.
Command
Install-Package Microsoft.EntityFrameworkCore.SqlServer -v 1.1.1
I add SqlServer and Sqlite to my project, the same problem arises.
For me, I installed Microsoft.EntityFrameworkCore earlier, it's version is 5.0.6. Now Microsoft.EntityFrameworkCore.SqlServer version is 5.0.7. There is no UserSqlServer method after installation.
1. Try to upgrade the tool version to be consistent
Try to modify the version in csproj:
<PackageReference Include="Microsoft.EntityFrameworkCore" Version="5.0.7">
Or open NuGet to update the package.
2. Restart your Visual Studio
If it won't help you, the most important thing is to restart VS
And then, everything is OK.
reference
https://github.com/dotnet/efcore/issues/7891
For me this issue happened with Visual Studio Code and I was able to fix with 2 steps:
Manually adding using Microsoft.EntityFrameworkCore;
Running dotnet build in terminal.
first add Install-Package Microsoft.EntityFrameworkCore.SqlServer
next add in your .cs file using Microsoft.EntityFrameworkCore;
finally add this in your core Startup.cs
public void ConfigureServices(IServiceCollection services)
{
services.AddEntityFrameworkSqlServer().AddDbContext<ApplicationContext>(options => options.UseSqlServer(Configuration.GetConnectionString("MovieContext")));
}
For anyone still having this problem:
Use NuGet to install:
Microsoft.EntityFrameworkCore.Proxies
This problem is related to the use of Castle Proxy with EFCore.
Wow so many answers yet none mentioned this Microsoft.EntityFrameworkCore.InMemory package!
Add the reference to this package:
<PackageReference Include="Microsoft.EntityFrameworkCore.InMemory" Version="2.2.2" /> and you should be good to go.
If you are facing this issue in case of Sqlite then
.
I think this is the problem with version of Sqlite,I had the same problem when I was using this versions of SqLite
Version 2.2.4:
After checking version here I changed the version then it worked.
No error after using this
Version 2.1.2:
Easy way to fix this issue
Error message:
Solution:
to install "microsoft.entityframeworkcore.sqlserver" with NuGet
Fixed :
PS: make sure you have using EF on the content "using Microsoft.EntityFrameworkCore;"
I read and did everything instructed in every answer and I just found out my problem was a missing constructor on my DbContext
public Context(DbContextOptions<Context> options) : base(options) { }
I hope this helps anyone facing the same problem I was.
I got around this by simply:
Add SqlServerDbContextOptionsExtensions to the class in question
Resolve SqlServerDbContextOptionsExtensions
This fixes the issue, must be missing some reference by default.
I had this trouble when I moved to Microsoft.EntityFrameworkCore.SqlServer v3.0.0 and Microsoft.EntityFrameworkCore.Tools v3.0.0
When I changed back to v2.2.6 on both libraries, the error went away. This is more of a workaround than a solution but it'll get you up and running till the issue is fixed.
Currently working with Entity Framework Core 3.1.3. None of the above solutions fixed my issue.
However, installing the package Microsoft.EntityFrameworkCore.Proxies on my project fixed the issue. Now I can access the UseLazyLoadingProxies() method call when setting my DBContext options.
Hope this helps someone. See the following article:
Lazy Loading in EF Core
For asp.net core version 2.1 make sure to add the following package to fix the problem. (At least this fix the issue using SQLite)
dotnet add package Microsoft.EntityFrameworkCore.Sqlite
dotnet add package Microsoft.EntityFrameworkCore.Design
Here is the reference of the documentation using SQLite with entity framework core.
https://learn.microsoft.com/en-us/ef/core/get-started/netcore/new-db-sqlite
I had this issue, it seems that I hadn't added the required NuGet packages, although I thought I had done so, make sure to check them, one by one.
Install-Package:
**Microsoft.EntityFrameworkCore.SqlServer**
then add the top of your class:
**Microsoft.EntityFrameworkCore;**
that's worked for me
I am new to .NET platform. From time to time, I had problems with Visual Studio and I decided to use Rider. It encouraged me again (I have been using JetBrains products for 2 years). But I can not find the NuGet console (which is so called in Visual Studio).
Where is it?
It's not accessible yet. Please vote this issue https://youtrack.jetbrains.com/issue/RIDER-435
It is available since Rider 2018.1.
Please see JetBrains' blog post about installation: https://blog.jetbrains.com/dotnet/2018/04/06/entity-framework-support-rider-2018-1/
P.S. tested on Rider 2020.2.1.
You Can use PowerShell on Windows "Where Your DbContext is" Like this:
dotnet ef
dotnet ef migrations add [Name]
If you need to run entity framework commands such as
dotnet ef migrations add "initialSetup"
Then go to your terminal Alt+f12 or double-shift and type “terminal”.
Then run:
dotnet tool install --global dotnet-ef
And then (making sure you're in your project directory):
dotnet ef migrations add "initialSetup"
Although Rider has now added the UI for migration, unfortunately, if you use the latest dotnet feature the UI doesn't work.
For example, I created the project without Startup class file, the UI won't let me continue:
But I tried these commands which works:
dotnet tool install --global dotnet-ef
# You can type the DbContext manually now!
dotnet ef migrations add 'initial' --project src/IdentityServer/IdentityServer.csproj --context PersistedGrantDbContext
Then I execute:
dotnet ef database update --project src/IdentityServer/IdentityServer.csproj --context ConfigurationDbContext
Now the database updated with all the tables there:
They haven't implemented the Package manager console yet. So you will have to use Visual studio for that
You can use terminal toolwindow. Or NuGet manager (GUI)...
I have ASP.NET Core (v1.0.0-preview2-003131) installed on my macOS Sierra, and installed yeoman generator-aspnet today(11/26/16). From my cli, I ran yo aspnet and created my WebApplication but the options shown to use were dnu restore, dnu build, dnx . kestrel.
What happened to dotnet restore option? I even tried to run dotnet restore but it kept on looking for dnu.
No, DNU is part of the old DNX which was used up until rc1. RC2 and newer are based on dotnet-cli and the dotnet commands.
DNX isn't maintained anymore and shouldn't be use anymore. Just use the dotnet commands, ignoring what that generator says and report the issue here.