Day: May 4, 2025

PostgreSQL PostgreSQL Interview Questions and Answers Section 1: PostgreSQL Architecture & Internals (20+ Questions) 1. What is the architecture of PostgreSQL? PostgreSQL follows a client-server model. It consists of the following key components: Postmaster (master process) Backend Server Processes (handle queries) Shared Buffers WAL (Write-Ahead Logging) Background Writer and Checkpointer 2. What is a WAL […]

Redis Redis Interview Questions and Answers What is Redis? – Redis is an in-memory, key-value data store known for high performance, supporting data structures such as strings, hashes, lists, sets, sorted sets. What data types does Redis support? – Strings, Lists, Sets, Sorted Sets (zsets), Hashes, Bitmaps, HyperLogLogs, Streams, and Geospatial indexes. How do you […]

DOCKER DOCKER Interview Questions and Answers 1. What is Docker, and how is it different from a virtual machine? Answer: Docker is a platform for developing, shipping, and running applications in containers. Unlike virtual machines (which virtualize hardware), Docker virtualizes the OS, making it lightweight and faster to start. Feature Virtual Machine Docker Virtualizes Hardware […]

DSA DSA Interview Questions and Answers 1. Find the First Non-Repeating Character in a String Problem: Given a string s, find the first non-repeating character and return its index. If none exists, return -1. JavaScript: function firstUniqChar(s) { const freq = {}; for (let char of s) { freq[char] = (freq[char] || 0) + 1; […]