.NET / EF Core - 60+ Practical Interview Questions

Updating a villa fails when the posted data lacks an id, causing EF Core to create a new villa. Add a hidden id field and update when villa.id > 0.

Improve the index action by replacing a multi-line if with a ternary operator for null or empty titles defaulting to dotnet mastery, and adopt string interpolation with the dollar sign.

The lecture shows how to fetch a villa's amenities by using include with no tracking to retrieve the first villa amenity for villa ID one, such as private pool.

The home controller fetches villa by id and uses is null instead of == to avoid overridden equality; return error view or villa view.

The lecture demonstrates retrieving villa and amenity in the home controller with a where condition and order by. It emphasizes readability by formatting chained calls with one dot per line.

Shows how to optimize an EF Core query by applying split queries to load villa amenities, categories, pricing, and specialties without Cartesian explosion, and considers stored procedures as an alternative.

Optimize the update pricing action by running three async services in parallel with Task.WhenAll to cut total execution time, highlighting that the duration is driven by the longest task.

Identify and implement clean code improvements by replacing string concatenation in a loop with a string builder, then streamline villa summary view model initialization for better architecture.

Use first or default with a predicate in EF Core to fetch a single record, letting EF Core consolidate the query; apply await with FirstOrDefaultAsync for async safety.

Learn how to override a base class method in a console app to print 'welcome from class B' within an a-b-c inheritance and the role of the override keyword.

Convert a string utility into a static string extension using the this keyword to trim and collapse spaces, then apply it in the home controller and application builder.