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SQLite with EntityFramework Exception: Cannot open database requested by the login

App.config file:
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<configSections>
<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
</configSections>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.7.2" />
</startup>
<entityFramework>
<providers>
<provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
<provider invariantName="System.Data.SQLite" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" />
<provider invariantName="System.Data.SQLite.EF6" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" />
</providers>
</entityFramework>
<system.data>
<DbProviderFactories>
<add name="SQLiteConnection" providerName="System.Data.SQLite.EF6" connectionString="Data Source=C:\Users\wzz\source\repos\PutixinEditor\PutixinEditor\db.sqlite" />
</DbProviderFactories>
</system.data>
</configuration>
my dbContext:
class PutixinDbContext : DbContext
{
public PutixinDbContext() : base("SQLiteConnection")
{
Database.SetInitializer<PutixinDbContext>(null);
}
public DbSet<Category> Category { get; set; }
}
But when I context.SaveChanges(), error throw:
SqlException: Cannot open database "SQLiteConnection" requested by the login. The login failed.
Login failed for user 'DESKTOP-BR8U8NG\wzz'.
I am using Visual Studio 2019

Error: "System.Data.SqlClient.SqlException: Cannot open database "MyDatabase" requested by the login. The login failed.
Login failed for user 'MyComputer\myUser'."
The error is very misleading because in your case, it will happen even if the the user has full permissions to write to the file and directory in question, in your case directory C:\Users\wzz\source\repos\PutixinEditor\PutixinEditor\ and file C:\Users\wzz\source\repos\PutixinEditor\PutixinEditor\db.sqlite.
The name of the string parameter passed to the DBContext constructor is "nameOrConnectionString". You are not passing a connection string, but instead your provider name. You have no such connection string.
As per Microsofts documentation, since no such connection string is found, the name is passed to the DefaultConnectionFactory, which wants to connect to a MsSQL or SqlExpress database. This is probably where the "Login failed" message comes from.
However,there is no ConnectionFactory class in System.Data.Sqlite.EF6 (v4.0.30319) which you could use instead.
Here is what will work: Create and name a separate connection string:
<connectionStrings>
<add name="SQLiteConnection" connectionString="data source=C:\Users\wzz\source\repos\PutixinEditor\PutixinEditor\db.sqlite;foreign keys=true" providerName="System.Data.SQLite" />
</connectionStrings>
You also have to configure the corresponding ProviderFactory, or else you'll get an error about not finding the requested provider
(With the friendly message "The ADO.NET provider with invariant name 'System.Data.SQLite' is either not registered in the machine or application config file, or could not be loaded.").
The provider factory you need is System.Data.SQLite.SQLiteFactory (from the System.Data.SQLite assembly).
<DbProviderFactories>
<add name="SQLite Data Provider" invariant="System.Data.SQLite" description=".NET Framework Data Provider for SQLite" type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite" />
</DbProviderFactories>
Now your DbContext should work.
I got the same error when I misspelled the name of the connection string in the constructor of the DbContext. It was very confusing because there was absolutely nothing wrong with the permissions of the sqlite file.

Postgresql and Entity Framework

In my project I am trying to use Entity Framework along with PostgreSql. But I am not able to connect to my database. I am not getting any error, it just gets stuck. I think something is wrong with my app.config, but I am not able to find out what.
App.config:
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<configSections>
<section name="entityFramework"
type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
</configSections>
<entityFramework>
<defaultConnectionFactory type="Npgsql.NpgsqlFactory, Npgsql" />
<providers>
<provider invariantName="Npgsql"
type="Npgsql.NpgsqlServices, Npgsql.EntityFramework" />
</providers>
</entityFramework>
<system.data>
<DbProviderFactories>
<add name="Npgsql Data Provider" invariant="Npgsql"
description="Data Provider for PostgreSQL"
type="Npgsql.NpgsqlFactory, Npgsql" />
</DbProviderFactories>
</system.data>
<connectionStrings>
<add name="Entities"
connectionString="server=localhost;user id=postgres;password=4321;database=postgis"
providerName="Npgsql" />
</connectionStrings>
</configuration>
DbContext:
public class Entities : DbContext
{
public Entities() : base("Entities")
{
}
//rest of the code
}
mycode.cs
using (var db = new Entities()) // when debug it stuck here and keep running
{
// some test code
}
EDIT:
I get the following error :
"The Entity Framework provider type 'Npgsql.NpgsqlServices, Npgsql.EntityFramework' registered in the application config file for the ADO.NET provider with invariant name 'Npgsql' could not be loaded. Make sure that the assembly-qualified name is used and that the assembly is available to the running application.

The problem points to a wrong provider type or assembly name.
<entityFramework>
<defaultConnectionFactory type="Npgsql.NpgsqlFactory, Npgsql" />
<providers>
<provider invariantName="Npgsql"
type="Npgsql.NpgsqlServices, Npgsql.EntityFramework" />
</providers>
</entityFramework>
The assembly name is wrong. The assembly installed by the EntityFramework6.Npgsql package is EntityFramework6.Npgsql.dll. In fact, adding the package to a new project sets the correct provider line:
<providers>
<provider invariantName="Npgsql" type="Npgsql.NpgsqlServices, EntityFramework6.Npgsql" />
</providers>

Entity Framework To A Remote Server (Connection String)

I have installed EF Version 6.1.3 on all my projects. I then created a model class, a context class, and installed a MSSQL database on my local computer (I did not have done anything else). Everything worked just perfectly (somehow it knew about my local database).
Model class:
public class Account
{
public int Id { get; set; }
public string Name{ get; set; }
}
DataContext class:
public class MyClassDataContext: DbContext
{
public DbSet<Account> Accounts{ get; set; }
}
App.config:
<?xml version="1.0" encoding="utf-8"?>
<configuration>
<configSections>
<!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=xxxxxx" requirePermission="false" />
</configSections>
<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
<providers>
<provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
</providers>
</entityFramework>
</configuration>
I then tried to move it to a remote database and it doesn't work. I tried everything.
What is the right approach, to get the job done?
EDIT:
I tried this connection string and nothing happens. The app still tries to connect with the local database.
<connectionStrings>
<add name="MyClassDataContext" connectionString="Data Source=MyRemoteServer;Initial Catalog=MyRemoteCatalog;Integrated Security=true" providerName="System.Data.SqlClient"/>
</connectionStrings>
<configSections>

You need to create either make sure that your connections string's name is the fully qualified name of your context, or create an explicit default constructor for your context. Since you mentioned it in the comments, the link you provided isn't working for you because you're using code-first. Try this link instead.
Below is a fully functional console app that can demonstrate how it should work, along with the config file. This will use our local SQLServer installation, but not the SQLExpress. It should work fine for any remote database as well.
Note that in the previous app config that I had posted, I put the connection string section at the top. That is incorrect: configSections must be the first node.
namespace TestApp
{
public class Account
{
public int Id { get; set; }
public string Name { get; set; }
}
public class MyClassDataContext : DbContext
{
public DbSet<Account> Accounts { get; set; }
}
class Program
{
static void Main(string[] args)
{
using (var x = new MyClassDataContext())
{
x.Accounts.Add(new Account { Name = "Drew" });
x.SaveChanges();
var y = x.Accounts;
foreach (var s in y)
{
Console.WriteLine(s.Name);
}
}
Console.ReadKey();
}
}
}
The configuration file:
<configuration>
<configSections>
<!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
</configSections>
<connectionStrings>
<add name="ConsoleApplication4.MyClassDataContext" connectionString="Data Source=.;Initial Catalog=MyClass;Integrated Security=true" providerName="System.Data.SqlClient"/>
</connectionStrings>
<startup>
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.2" />
</startup>
<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
<parameters>
<parameter value="mssqllocaldb" />
</parameters>
</defaultConnectionFactory>
<providers>
<provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
</providers>
</entityFramework>
</configuration>

Asp.Net MVC - Access to Postgresql with Entity Framework + Npgsql.Entityframework

I'm creating an ASP.NET MVC application which uses a PostgreSql database. Model classes are in a different class library. For access to database i'm using Entity Framework + Npgsql.Entityframework from Nuget in the class library. Also i added same links to main project. Configuration settings are in web.config of main project:
<configSections>
<section name="entityFramework"
type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"
requirePermission="false" />
</configSections>
<entityFramework>
<defaultConnectionFactory type="Npgsql.NpgsqlServices, Npgsql.EntityFramework" />
<providers>
<provider invariantName="Npgsql"
type="Npgsql.NpgsqlServices, Npgsql.EntityFramework" />
</providers>
</entityFramework>
<connectionStrings>
<add name="NpgsqlContext"
providerName="Npgsql"
connectionString="Server=127.0.0.1;User Id=BaseId;Password=BasePass;Port=5432;Database=Base;" />
</connectionStrings>
<system.data>
<DbProviderFactories>
<add name="Npgsql Data Provider"
invariant="Npgsql"
support="FF"
description=".Net Framework Data Provider for Postgresql"
type="Npgsql.NpgsqlFactory, Npgsql" />
</DbProviderFactories>
</system.data>
I created database and some tables in pgAdmin. To access to base and tables i use classes (example):
public class NpgsqlContext : DbContext
{
public NpgsqlContext(): base(nameOrConnectionString: "NpgsqlContext")
{
}
public DbSet<BaseArticle> BaseArticles { get; set; }
}
[Table("ARTICLE", Schema = "public")]
public class BaseArticle
{
[Key]
[Column("ID")]
public int Id { get; set; }
[Column("DATETIME")]
public DateTime DateTime { get; set; }
[Column("TITLE")]
public string Title { get; set; }
[Column("BODY")]
public string Body { get; set; }
}
NpgsqlContext object is created normally and has right connectionn string (PORT=5432;KRBSRVNAME=name;TIMEOUT=15;POOLING=True;MINPOOLSIZE=1;MAXPOOLSIZE=20;COMMANDTIMEOUT=20;COMPATIBLE=2.2.7.0;HOST=127.0.0.1;USER ID=BasePass;PASSWORD=BasePass;DATABASE=Base), but didn't see any records in datatable in base - DbSet BaseArticle's count equals 0. Meanwhile records are there. Where can i have an error?
And also - in ASP.NET MVC generally impossible to achieve loose coupling between the parts of the application? For example - i created ASP.NET MVC application and carried out classes of access to a database in separate libraries. But i had to indicate links to the packages from Nuget in the main project. How could I avoid it?

For the solution of my problem i needed to open connection to base in constructor of context:
this.Database.Connection.Open();

Unable to determine the provider name for provider factory of type "System.Data.Sqlite.SqliteFactory"

I want to use sqlite entity framework in my web api project, but it always can't work well,
here is my development enviroment.
1.Visual studio 2013, .net framework 4.5
sqlite package version is 1.0.97, I installed below packages
system.data.sqlite,
system.data.sqlite.ef6,
system.data.sqlite.linq
EntityFramework is 6.1.3
Here is exception that I got
Unable to determine the provider name for provider factory of type 'System.Data.SQLite.SQLiteFactory'. Make sure that the ADO.NET provider is installed or registered in the application config
Here is my webconfig
<configuration>
<configSections>
<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
<!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
</configSections>
<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
<parameters>
<parameter value="mssqllocaldb" />
</parameters>
</defaultConnectionFactory>
<providers>
<provider invariantName="System.Data.SQLite.EF6" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" /> <!--type="System.Data.SQLite.EF6.SQLiteProviderServices-->
</providers>
</entityFramework>
<system.data>
<DbProviderFactories>
<remove invariant="System.Data.SQLite.EF6" />
<add name="SQLite Data Provider (Entity Framework 6)" invariant="System.Data.SQLite.EF6" description=".NET Framework Data Provider for SQLite (Entity Framework 6)" type="System.Data.SQLite.EF6.SQLiteProviderFactory, System.Data.SQLite.EF6" />
</DbProviderFactories>
</system.data>
<connectionStrings>
<add name="Sqlite" connectionString="data source="D:\MyWebAPI\src\MyWeb.Api\App_Data\sqlite_test.db"" providerName="System.Data.SQLite.EF6" />
</connectionStrings>
</configuration>
I can connect sqlite database file through "connect to database" in tool of visual studio, I also can generate entity using code first.
but I can't get data normal
Here is my code
public partial class Sqlite : DbContext
{
public Sqlite()
: base("name=Sqlite")
{
}
public virtual DbSet<AuthorizationLog> AuthorizationLogs { get; set; }
public virtual DbSet<Checksum> Checksums { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<AuthorizationLog>()
.Property(e => e.ClientKey)
.IsUnicode(false);
modelBuilder.Entity<AuthorizationLog>()
.Property(e => e.Login)
.IsUnicode(false);
modelBuilder.Entity<AuthorizationLog>()
.Property(e => e.Password)
.IsUnicode(false);
modelBuilder.Entity<AuthorizationLog>()
.Property(e => e.ConnectionString)
.IsUnicode(false);
}
}
public class ValuesController : ApiController
{
// GET api/values
Sqlite ctx = new WebApi2Demo.Sqlite();
public IEnumerable<Checksum> Get()
{
return ctx.Checksums;
}
}

I got the answer by myself, but I still don't know the root cause, now it works. I changed webconfig, here is the webconfig that make my project to work.
I added a provider that is "System.Data.Sqlite", Please note its type that is same with System.Data.Sqlite.EF6
<provider invariantName="System.Data.SQLite" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" />
<add name="SQLite Data Provider" invariant="System.Data.SQLite" description=".NET Framework Data Provider for SQLite" type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite" />
<remove invariant="System.Data.SQLite.EF6" />
Here is all configure.
<entityFramework>
<providers>
<provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
<provider invariantName="System.Data.SQLite.EF6" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" />
<provider invariantName="System.Data.SQLite" type="System.Data.SQLite.EF6.SQLiteProviderServices, System.Data.SQLite.EF6" />
</providers>
</entityFramework>
<system.data>
<DbProviderFactories>
<remove invariant="System.Data.SQLite" />
<add name="SQLite Data Provider" invariant="System.Data.SQLite" description=".NET Framework Data Provider for SQLite" type="System.Data.SQLite.SQLiteFactory, System.Data.SQLite" />
<remove invariant="System.Data.SQLite.EF6" />
<add name="SQLite Data Provider (Entity Framework 6)" invariant="System.Data.SQLite.EF6" description=".NET Framework Data Provider for SQLite (Entity Framework 6)" type="System.Data.SQLite.EF6.SQLiteProviderFactory, System.Data.SQLite.EF6" />
</DbProviderFactories>
</system.data>

That was a super-great answer zhnglicho!
Another option, aside from placing the providers and DbProviderFactories into the app.config or web.config, is to code your ProviderFactories and use it in your implementation of DbContext.
Usings:
using System.Data.Entity;
using System.Data.Entity.Core.Common;
using System.Data.Entity.ModelConfiguration.Conventions;
using System.Data.SQLite;
using System.Data.SQLite.EF6;
Config Class:
public class SQLiteConfiguration : DbConfiguration
{
public SQLiteConfiguration()
{
SetProviderFactory("System.Data.SQLite", SQLiteFactory.Instance);
SetProviderFactory("System.Data.SQLite.EF6", SQLiteProviderFactory.Instance);
SetProviderServices("System.Data.SQLite", (DbProviderServices)SQLiteProviderFactory.Instance.GetService(typeof(DbProviderServices)));
}
}
Place this in your constructor:
public PythonContext() : base($"name=pythonSource")
{
DbConfiguration.SetConfiguration(new SQLiteConfiguration());
}
I've run unit tests against both methods (this one and the zhnglicho answer) and i've not found any speed differences.
Debug Output (getting a record count and a random quote from the sqlitedb):
Found 18307 Records
Presenter: 'And Miles Yellowbird, up high in banana tree, the golfer and
inventor of Catholicism.'
Debug Trace:
Native library pre-loader is trying to load native SQLite library "C:\Users\***\***\\SQLiteTests\bin\Debug\x64\SQLite.Interop.dll"...
I up-voted the previous answer as it worked for me, but this is just a suggestion if you don't want to jack with your configs. ~ PEACE!
sqlite entityframework