Example: One Category has many Products. EF Core uses a Foreign Key in the child table. Professional tip: Use Shadow Properties for FK IDs to keep your domain models clean.
In modern .NET, you no longer need a manual joining entity class for simple many-to-many relationships. EF Core manages the hidden join table automatically!
Example: One User has one Profile. The Profile table's Primary Key is also its Foreign Key. This ensures absolute data integrity at the database level.
Always explicitly configure your Delete Behavior in Fluent API. Use OnDelete(DeleteBehavior.Restrict) to prevent accidental mass deletion of orders when a user is deleted in your system. This is a critical security and data safety audit point!