Entity Framework Core — DbContext, migrations, relationships, and query optimization with LINQ.
Five passes over the same idea, each from a different angle. Do them in order, or jump to whichever you need.
EF Core is .NET's ORM for database access. Key concepts: DbContext, entity configuration (Fluent API vs data annotations), migrations, relationships (1:1, 1:N, N:N), lazy/eager/explicit loading, change tracking, raw SQL, and performance optimization (split queries, projections, compiled queries).
