Q1. What are the Redis data structures and what is each used for?
Redis exposes several core data types, each with tailored commands. - Strings: counters, cached serialized objects and rate limiters using INCR and SETEX. - Hashes: objec...
Technical Question Bank · Peer-Reviewed
Job Interview Questions and Answers Directory
Search and filter frequently asked interview questions across technical, programming, and behavioral domains. Tailor your interview preparation by difficulty for freshers or experienced developers (20 available).
Active:
Tag: cac ×
Q2. What is caching and why is it used?
Caching stores a copy of data in a faster or closer tier so future reads avoid the slower origin. It reduces latency, increases throughput, lowers load and cost on databa...
Q3. How would you design a URL shortener like bit.ly?
Requirements: shorten a long URL, redirect quickly, handle ~100M new links per day with a 100:1 read-to-write ratio. API: POST /api/links {longUrl} -> {shortUrl}; GET /{c...
Q4. Explain Docker layers and how caching works.
A Docker image is a stack of read-only layers. Each Dockerfile instruction creates a layer, and layers are shared between images and cached. Build cache: - Docker checks ...
Q5. What is the difference between cache-aside and read-through?
Cache-aside (lazy loading): the application checks the cache first. On a miss it reads the database, then writes the value into the cache and returns it. The application ...
Q6. What does a CDN cache and how does it help?
A content delivery network caches content on edge servers close to users. It serves static assets such as images, CSS, JavaScript and fonts, and can cache dynamic respons...
Q7. Explain caching strategies and common failure modes.
Strategies: - Cache-aside (lazy loading): app checks cache, on miss reads DB and populates. Most common. - Read-through: cache library fetches on miss. - Write-through: w...
Q8. Describe how DNS resolution works.
DNS maps names to records, most importantly A and AAAA addresses, plus CNAME, MX, TXT and NS. A lookup can walk several servers, but caching means most lookups stop early...
Q9. What is the cache-aside pattern and how do you keep the cache consistent?
In cache-aside the application checks the cache first. On a miss it reads from the database, writes the value into the cache with a TTL, and returns it. On writes, the co...
Q10. How does data fetching and caching work in the App Router?
You fetch inside async Server Components using the extended fetch: ```ts const res = await fetch('https://api.example.com/posts', { next: { revalidate: 60, tags: ['posts'...