Entity Framework Core Study Notes

Applying and Reverting Migrations

How to apply pending migrations to a database, generate deployable SQL scripts, and safely roll back schema changes.

Avoiding the N+1 Query Problem

How lazy loading silently causes one query per entity in a loop, and how Include, projection, and split queries fix it in EF Core.

Change Tracking Explained

How EF Core's ChangeTracker snapshots entity state and computes the minimal set of INSERT, UPDATE, and DELETE statements needed at SaveChanges time.

Code-First vs Database-First

Comparing the Code-First and Database-First workflows in EF Core and how to choose between them, including hybrid approaches.

Optimistic Concurrency Control

How EF Core detects and resolves concurrent edit conflicts using concurrency tokens and DbUpdateConcurrencyException, and how this compares to pessimistic lock…

Data Annotations vs Fluent API

Compare EF Core's two configuration approaches - inline Data Annotations and the more powerful Fluent API - and learn when each is the right tool.

DbContext and DbSet

How DbContext and DbSet work together as EF Core's session and table-collection abstractions, including change tracking and fluent configuration.

Eager, Lazy, and Explicit Loading

The three strategies EF Core offers for loading related data, and how choosing the wrong one causes the N+1 query problem.

EF Core Best Practices

A practical checklist of habits that keep EF Core applications fast, predictable, and maintainable as they scale.

EF Core Interview Questions

Common EF Core interview topics — change tracking, migrations, loading strategies, and concurrency — explained with the reasoning behind strong answers.

EF Core Quick Reference

A condensed reference of the EF Core CLI commands, LINQ query patterns, and configuration APIs you reach for most often.

EF Core vs Dapper

A comparison of EF Core's full ORM feature set against Dapper's lightweight micro-ORM approach, and how to choose or combine them.

Entity Classes and Conventions

Learn how EF Core discovers and maps plain C# classes to database tables using convention-based modeling, including primary keys, shadow properties, and backin…

Filtering, Sorting, and Paging

Building efficient, parameterized queries with Where, OrderBy, and Skip/Take, plus the tradeoffs of offset versus keyset pagination.

Handling Schema Drift in Teams

Strategies for detecting and resolving mismatches between the EF Core model, migration history, and the actual database schema across a team.

Installing and Configuring EF Core

Step-by-step guide to installing EF Core NuGet packages, configuring connection strings, and registering DbContext with dependency injection.

LINQ to Entities

How EF Core translates LINQ query syntax into SQL, and the rules that govern what can and cannot be pushed down to the database.

Migrations Fundamentals

Learn how EF Core migrations track model changes and generate versioned database schema updates while preserving existing data.

Migrations in CI/CD Pipelines

Patterns for safely automating EF Core migration deployment within continuous integration and delivery pipelines, including zero-downtime strategies.

Projections with Select

Using Select to shape query results into DTOs, reducing data transfer and avoiding unnecessary change tracking overhead.

Raw SQL Queries with FromSqlRaw

When and how to drop down to raw SQL in EF Core with FromSqlRaw and FromSqlInterpolated, and how to do it without opening a SQL injection hole.

Many-to-Many Relationships

Learn how EF Core models many-to-many relationships with skip navigations, implicit join tables, and explicit join entities that carry payload data.

One-to-Many Relationships

Learn how EF Core models one-to-many relationships through navigation properties and foreign keys, including required vs optional relationships and delete beha…

Seeding Data

Techniques for populating a database with initial or reference data using EF Core, from model-based HasData to imperative startup seeding.