Tutorials ASP.NET Core MVC Mastery
Relationships
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Mastering EF Core Relationships (Database Architecture)
1. One-to-Many (The Standard)
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.
2. Many-to-Many (.NET 5.0+ Revolution)
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!
3. One-to-One (The Master-Detail)
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.
Architect Insight: Cascading Deletes
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!