Laravel PHP Developer Jobs in Noida

Top 10 Laravel Interview Questions for Yes IT Labs Noida (2-5 Years Experience)

Q1. What are Queues in Laravel and when should you use them?
Ans. Queues let you move slow work, such as sending emails, generating PDFs or calling third-party APIs, out of the web request and run it in the background. You create a job class that implements ShouldQueue, send it with dispatch(), and a worker started with "php artisan queue:work" processes it. The user gets a fast response, and failed jobs are saved in the failed_jobs table so they can be retried.

Q2. What is Middleware and how have you used it?
Ans. Middleware is a layer that checks or changes a request before it reaches the controller. The built-in "auth" middleware sends guests to the login page. Developers also write custom middleware, for example to block inactive accounts or to allow only admins into a section. It is created with "php artisan make:middleware" and attached to routes or route groups.

Q3. What is Route Model Binding?
Ans. When a route parameter is type-hinted with a model, for example Route::get('/jobs/{job}', ...) with "Job $job" in the controller, Laravel fetches the record automatically and returns a 404 if it does not exist. You can bind by another column, such as a slug, with {job:slug}. This removes repeated findOrFail() code from controllers.

Q4. What is Mass Assignment and how do you protect against it?
Ans. Mass assignment means filling many model fields at once, as in User::create($request->all()). If it is not controlled, a user could send an extra field like "is_admin=1". Laravel protects against this with the $fillable property (a list of allowed fields) or $guarded (a list of blocked fields). Passing only validated data, such as $request->validated(), adds another layer of safety.

Q5. How do Database Transactions work in Laravel?
Ans. DB::transaction() runs a group of queries as a single unit. If any query inside the closure throws an exception, every change is rolled back. This matters when several tables must stay in sync, for example creating an order, reducing stock and saving the payment record together.

Q6. How do you use caching to make a Laravel application faster?
Ans. Cache::remember('key', $seconds, function () { ... }) returns the cached value if it exists. Otherwise it runs the query, stores the result and returns it. This works well for data that is read often and changes rarely, such as category lists or settings. In production, Redis is a common cache driver, and the related cache key should be cleared whenever that data is updated.

Q7. What are Soft Deletes?
Ans. With the SoftDeletes trait and a deleted_at column, calling delete() does not remove the row. It only sets the deleted_at timestamp, and normal queries hide that record automatically. withTrashed() includes deleted records, restore() brings a record back, and forceDelete() removes it permanently. It is useful wherever data must be recoverable or kept for audit history.

Q8. How do you process a very large table without running out of memory?
Ans. Loading lakhs of rows with get() puts all of them in memory at once. chunk(500) loads 500 rows per query and processes them batch by batch, and chunkById() is safer when you are updating the same rows while looping. cursor() or lazy() fetch records one by one using PHP generators, which keeps memory use very low.

Q9. What are API Resources in Laravel?
Ans. An API Resource (a class extending JsonResource) controls exactly how a model is converted to JSON. You choose which fields to return, can rename or format them, and can hide sensitive columns. whenLoaded() includes a relationship only if it was already loaded. This keeps the API response format consistent even if the database structure changes.

Q10. How do you secure an API using Laravel Sanctum?
Ans. Sanctum provides simple token-based authentication for mobile apps and SPAs. After login, $user->createToken('app')->plainTextToken creates a token that the client sends in the Authorization: Bearer header. Routes protected with the auth:sanctum middleware accept only valid tokens. Tokens can be given limited permissions (abilities) and can be revoked at any time.