After the Update-DataBase migration command, A database with the same name exists error

Question

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)
        {
            
        }
    }
}