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advanced patterns with C# Code First Migrations and Existing Database Connections

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entity-framework-core database migrations sql-server csharp

I'm learning this framework and I'm relatively new to this, so bear with me. I'm sure I'm missing something obvious here, but I'm working on a personal project and I'm working with an scenario with Entity Framework Core 6 while trying to apply Code First migrations to an existing database. The database is already populated, and I'm using a local SQL Server instance. When I run `Update-Database` from the Package Manager Console, I receive the following behavior: `The migration 'xxxx' is not compatible with the database`. I have ensured that my migration history is correctly set up in the `__EFMigrationsHistory` table, and I've double-checked that the connection string in my `appsettings.json` matches the database I intend to migrate. Here’s the relevant part of my `DbContext` class: ```csharp public class MyDbContext : DbContext { public MyDbContext(DbContextOptions<MyDbContext> options) : base(options) { } public DbSet<Product> Products { get; set; } // Other DbSets... protected override void OnModelCreating(ModelBuilder modelBuilder) { modelBuilder.Entity<Product>().ToTable("Products"); // Additional configurations... } } ``` Prior to running the migration, I manually updated my SQL Server database to match the current model structure by adding a few new columns. However, I did not create a corresponding migration before doing this. When I attempt to run `Update-Database`, it seems like EF is not recognizing these changes, and I’m worried I might lose existing data if I try to force the migration. I have tried regenerating the migrations using `Add-Migration` and ensuring that my local model matches the database schema, but I keep running into the same behavior. What steps should I take to resolve this scenario without losing any existing data in my database? Is there a recommended approach to handle migrations against an already populated database in EF Core? This is part of a larger service I'm building. What am I doing wrong? My development environment is Linux. Am I missing something obvious? Is this even possible? The stack includes Csharp and several other technologies. Any ideas how to fix this? I've been using Csharp for about a year now. Any ideas how to fix this?