After executing the migration command Update-DataBase -v.
I get an error.
An attempt to attach an auto-named database for file Bookinist.mdf failed.
A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
Question: How to fix the error and create a database using migration?
My expectations:
- create a layer "WPF Core3.1 application";
- create a layer for working with a database that will work with EFCore;
- Migrations should create a database in the layer where the application is located (Migration EF Wpf Core 31.v6).
Links
Project: MigrationEFWpfCore31.v6--github.com
Description
I did.
I have created a solution
appsettings.json
{
"ConnectionStrings": {
"DataBase": "Data Source=(localdb)\\MSSQLLocalDB;AttachDbFileName=Bookinist.mdf;Integrated Security=True"
}
}
App.xaml.cs
public partial class App : Application
{
public static IHostBuilder CreateHostBuilder(string[] args) => Microsoft.Extensions.Hosting.Host
.CreateDefaultBuilder(args)
.ConfigureServices(
(hostContext, services) => services
.AddDbContext<ContextDBBookinist>(opt =>
{
opt.UseSqlServer(hostContext.Configuration.GetConnectionString("Database"));
}
)
);
}
I opened the Package Manager Console.
I have installed The default project is - MigrationEFWpfCore31.v6.DAL.
Ran the Add-Migration Initial -v command.
I ran the Update-DataBase -v command.
An attempt to attach an auto-named database for file Bookinist.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
Solution-1. (Not working)
Project Solution-1. MigrationEFWpfCore31.v6--Test1--github.com
Added the App_Data folder
Added [DataDirectory]\\App_Data\\
Full code:
{
"ConnectionStrings": {
"DataBase": "Data Source=(localdb)\\MSSQLLocalDB;AttachDbFileName=[DataDirectory]\\App_Data\\Bookinist.mdf;Integrated Security=True"
}
}
App.xaml.cs
Added
string path = Directory.GetCurrentDirectory();
// ...
Configuration.GetConnectionString("DefaultConnection")
.Replace("[DataDirectory]", path)));
Full code:
public partial class App : Application
{
public static IHostBuilder CreateHostBuilder(string[] args) => Microsoft.Extensions.Hosting.Host
.CreateDefaultBuilder(args)
.ConfigureServices(
(hostContext, services) => services
.AddDbContext<ContextDBBookinist>(opt =>
{
string path = Directory.GetCurrentDirectory();
opt.UseSqlServer(hostContext.Configuration.GetConnectionString("Database")
.Replace("[DataDirectory]", path));
}
)
);
}
Package Manager Console
I entered the command Add-Migration Initial -v
I entered the command Update-DataBase -v
Error text:
An attempt to attach an auto-named database for file e:\Projects\Projects\5058\01_pr\01\MigrationEFWpfCore31.v6\MigrationEFWpfCore31.v6\App_Data\Bookinist.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.
Solution-2 (Did not check)
Maybe the migration works with a different version of MSSQLLocalDB, and in Microsoft SQL Server Management Studio am I seeing MSSQLLocalDB of a different version?
Note
Microsoft SQL Server Management Studio.
MigrationEFWpfCore31.v6
MigrationEFWpfCore31.v6.csproj
<Project Sdk="Microsoft.NET.Sdk.WindowsDesktop">
<PropertyGroup>
<OutputType>WinExe</OutputType>
<TargetFramework>netcoreapp3.1</TargetFramework>
<UseWPF>true</UseWPF>
</PropertyGroup>
<ItemGroup>
<PackageReference Include="Microsoft.EntityFrameworkCore" Version="5.0.0" />
<PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="5.0.0-rc.2.20475.6" />
<PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="7.0.0" />
<PackageReference Include="Microsoft.Extensions.Hosting" Version="5.0.0-rc.2.20475.5" />
<PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="5.0.0" />
</ItemGroup>
<ItemGroup>
<ProjectReference Include="..\MigrationEFWpfCore31.v6.DAL\MigrationEFWpfCore31.v6.DAL.csproj" />
</ItemGroup>
<ItemGroup>
<None Update="appsettings.json">
<CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
</None>
</ItemGroup>
<ItemGroup>
<Folder Include="App_Data\" />
</ItemGroup>
</Project>
MigrationEFWpfCore31.v6.DAL
MigrationEFWpfCore31.v6.DAL.csproj
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<TargetFramework>netstandard2.1</TargetFramework>
<Nullable>enable</Nullable>
</PropertyGroup>
<ItemGroup>
<PackageReference Include="Microsoft.EntityFrameworkCore" Version="5.0.0-rc.2.20475.6" />
<PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="5.0.0-rc.2.20475.6" />
</ItemGroup>
</Project>
Author.cs
using System.Collections.Generic;
namespace MigrationEFWpfCore31.v6.DAL.Entities
{
public class Author
{
public int AuthorId { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public List<Book> Books { get; set; }
}
}
Book.cs
namespace MigrationEFWpfCore31.v6.DAL.Entities
{
public class Book
{
public int BookId { get; set; }
public string Title { get; set; }
public Author Author { get; set; }
}
}
ContextDBBookinist.cs
using Microsoft.EntityFrameworkCore;
namespace MigrationEFWpfCore31.v6.DAL.Entities
{
public class ContextDBBookinist : DbContext
{
public DbSet<Author> Authors { get; set; }
public DbSet<Book> Books { get; set; }
public ContextDBBookinist(DbContextOptions<ContextDBBookinist> options) : base(options)
{
}
}
}
