Here are some tricky🧩 SQL interview questions!

1. Find the second-highest salary in a table without using LIMIT or TOP.

2. Write a SQL query to find all employees who earn more than their managers.

3. Find the duplicate rows in a table without using GROUP BY.

4. Write a SQL query to find the top 10% of earners in a table.

5. Find the cumulative sum of a column in a table.

6. Write a SQL query to find all employees who have never taken a leave.

7. Find the difference between the current row and the next row in a table.

8. Write a SQL query to find all departments with more than one employee.

9. Find the maximum value of a column for each group without using GROUP BY.

10. Write a SQL query to find all employees who have taken more than 3 leaves in a month.

These questions are designed to test your SQL skills, including your ability to write efficient queries, think creatively, and solve complex problems.

Here are the answers to these questions:

1. SELECT MAX(salary) FROM table WHERE salary NOT IN (SELECT MAX(salary) FROM table)

2. SELECT e1.* FROM employees e1 JOIN employees e2 ON e1.manager_id = (link unavailable) WHERE e1.salary > e2.salary

3. SELECT * FROM table WHERE rowid IN (SELECT rowid FROM table GROUP BY column HAVING COUNT(*) > 1)

4. SELECT * FROM table WHERE salary > (SELECT PERCENTILE_CONT(0.9) WITHIN GROUP (ORDER BY salary) FROM table)

5. SELECT column, SUM(column) OVER (ORDER BY rowid) FROM table

6. SELECT * FROM employees WHERE id NOT IN (SELECT employee_id FROM leaves)

7. SELECT *, column - LEAD(column) OVER (ORDER BY rowid) FROM table

8. SELECT department FROM employees GROUP BY department HAVING COUNT(*) > 1

9. SELECT MAX(column) FROM table WHERE column NOT IN (SELECT MAX(column) FROM table GROUP BY group_column)

🔥 Guys, Another Big Announcement!

I’m launching a Python Interview Series 🐍💼 — your complete guide to cracking Python interviews from beginner to advanced level!

This will be a week-by-week series designed to make you interview-ready — covering core concepts, coding questions, and real interview scenarios asked by top companies.

Here’s what’s coming your way 👇

🔹 Week 1: Python Fundamentals (Beginner Level)
• Data types, variables & operators
• If-else, loops & functions
• Input/output & basic problem-solving
💡 *Practice:* Reverse string, Prime check, Factorial, Palindrome

🔹 Week 2: Data Structures in Python
• Lists, Tuples, Sets, Dictionaries
• Comprehensions (list, dict, set)
• Sorting, searching, and nested structures
💡 *Practice:* Frequency count, remove duplicates, find max/min

🔹 Week 3: Functions, Modules & File Handling
• *args, *kwargs, lambda, map/filter/reduce
• File read/write, CSV handling
• Modules & imports
💡 *Practice:* Create custom functions, read data files, handle errors

🔹 Week 4: Object-Oriented Programming (OOP)
• Classes, objects, inheritance, polymorphism
• Encapsulation & abstraction
• Magic methods (__init__, __str__)
💡 *Practice:* Build a simple class like BankAccount or StudentSystem

🔹 Week 5: Exception Handling & Logging
• try-except-else-finally
• Custom exceptions
• Logging errors & debugging best practices
💡 *Practice:* File operations with proper error handling

🔹 Week 6: Advanced Python Concepts
• Decorators, generators, iterators
• Closures & context managers
• Shallow vs deep copy
💡 *Practice:* Create your own decorator, generator examples

🔹 Week 7: Pandas & NumPy for Data Analysis
• DataFrame basics, filtering & grouping
• Handling missing data
• NumPy arrays, slicing, and aggregation
💡 *Practice:* Analyze small CSV datasets

🔹 Week 8: Python for Analytics & Visualization
• Matplotlib, Seaborn basics
• Data summarization & correlation
• Building simple dashboards
💡 *Practice:* Visualize sales or user data

🔹 Week 9: Real Interview Questions (Intermediate–Advanced)
• 50+ Python interview questions with answers
• Common logical & coding tasks
• Real company-style questions (Infosys, TCS, Deloitte, etc.)
💡 *Practice:* Solve daily problem sets

🔹 Week 10: Final Interview Prep (Mock & Revision)
• End-to-end mock interviews
• Python project discussion tips
• Resume & GitHub portfolio guidance

📌 Each week includes:
✅ Key Concepts & Examples
✅ Coding Snippets & Practice Tasks
✅ Real Interview Q&A
✅ Mini Quiz & Discussion

👍 React ❤️ if you’re ready to master Python interviews!

👇 You can access it from here: https://whatsapp.com/channel/0029VaiM08SDuMRaGKd9Wv0L/2099

🚀 Front-End Development Interview Topics

HTML & CSS
🔹 Semantic HTML
🔹 CSS Pre-Processors
🔹 CSS Specificity
🔹 Resetting & Normalizing CSS
🔹 CSS Architecture
🔹 SVGs
🔹 Media Queries
🔹 CSS Display Property
🔹 CSS Position Property
🔹 CSS Frameworks
🔹 Pseudo Classes
🔹 Sprites

JavaScript
🔹 Event Delegation
🔹 Attributes vs Properties
🔹 Ternary Operators
🔹 Promises vs Callbacks
🔹 Single Page Application
🔹 Higher-Order Functions
🔹 == vs ===
🔹 Mutable vs Immutable
🔹 'this'
🔹 Prototypal Inheritance
🔹 IFE (Immediately Invoked Function Expression)
🔹 Closure
🔹 Null vs Undefined
🔹 OOP vs Map
🔹 .call & .apply
🔹 Hoisting
🔹 Objects
🔹 Scope
🔹 JS Frameworks

Data Structures and Algorithms
🔹 Linked Lists
🔹 Hash Tables
🔹 Stacks
🔹 Queues
🔹 Trees
🔹 Graphs
🔹 Arrays
🔹 Bubble Sort
🔹 Binary Search
🔹 Selection Sort
🔹 Quick Sort
🔹 Insertion Sort

Front-End Topics
🔹 Performance
🔹 Unit Testing
🔹 End-to-End Testing (E2E)
🔹 Web Accessibility
🔹 CORS
🔹 SEO
🔹 REST
🔹 APIs
🔹 HTTP/HTTPS
🔹 GitHub
🔹 Task Runners
🔹 Browser APIs

Javascript  for Everything:

JS + React = Web Development
JS + Three.js = 3D Visualization
JS + Angular = Web Applications

JS + Phaser = Game Development
JS + Vue.js = Progressive Web Apps
JS + TensorFlow.js = Machine Learning

JS + Node.js = Server-Side Development
JS + Electron = DesktopApp Development
JS + React Native = MobileApp Development

#javascript

List of Top 12 Coding Channels on WhatsApp:

1. Python Programming:
https://whatsapp.com/channel/0029VaiM08SDuMRaGKd9Wv0L


2. Coding Resources:
https://whatsapp.com/channel/0029VahiFZQ4o7qN54LTzB17


3. Coding Projects:
https://whatsapp.com/channel/0029VazkxJ62UPB7OQhBE502


4. Coding Interviews:
https://whatsapp.com/channel/0029VammZijATRSlLxywEC3X


5. Java Programming:
https://whatsapp.com/channel/0029VamdH5mHAdNMHMSBwg1s


6. Javascript:
https://whatsapp.com/channel/0029VavR9OxLtOjJTXrZNi32


7. Web Development:
https://whatsapp.com/channel/0029VaiSdWu4NVis9yNEE72z


8. Artificial Intelligence:
https://whatsapp.com/channel/0029VaoePz73bbV94yTh6V2E


9. Data Science:
https://whatsapp.com/channel/0029Va4QUHa6rsQjhITHK82y


10. Machine Learning:
https://whatsapp.com/channel/0029Va8v3eo1NCrQfGMseL2D


11. SQL:
https://whatsapp.com/channel/0029VanC5rODzgT6TiTGoa1v


12. GitHub:
https://whatsapp.com/channel/0029Vawixh9IXnlk7VfY6w43

ENJOY LEARNING 👍👍

🤩 Quick Roadmaps to Learn 🤩

❤️ Javascript

https://roadmap.sh/javascript

❤️ Data Science

https://miro.medium.com/max/828/1*UQ9M5X6R1LVPzwc4bfnt9w.webp

❤️ Frontend development
https://i0.wp.com/css-tricks.com/wp-content/uploads/2018/07/modern-front-end-developer.png?ssl=1

❤️ Data Analyst Roadmap

https://t.me/sqlspecialist/379

❤️ AI/ML

https://i.am.ai/roadmap

10 Python Mini Projects for Beginners

Guys, once you've got the basics of Python down, it’s time to build stuff!

Here are 10 mini project ideas that are fun, practical, and boost your confidence!

1. Number Guessing Game 🎯
The computer picks a number, and the user keeps guessing until they get it right.
Perfect to practice loops, conditionals, and user input.

2. Calculator App ➕➖✖️➗
Build a simple calculator that takes two numbers and performs addition, subtraction, multiplication, or division.

3. To-Do List (Console Version) ✅
Let users add, view, and delete tasks. Great to practice lists and file handling if you want to save tasks.

4. Password Generator 🔐
Create random passwords using letters, numbers, and symbols. Use the random and string modules.

5. Dice Rolling Simulator 🎲
Simulate rolling a die. Add cool features like rolling multiple dice or counting the frequency.

6. Rock Paper Scissors Game ✊✋✌️
Let the user play against the computer. Introduces randomness and conditional logic.

7. Quiz App ❓
Create a multiple-choice quiz that gives a score at the end. Store questions and answers using dictionaries.

8. Countdown Timer ⏱️
User inputs minutes or seconds, and the timer counts down to zero. Helps practice time.sleep().

9. Tip Calculator 🍽️
Calculate how much each person should pay including tip. Useful for string formatting and arithmetic.

10. Weather App (Using API) ☁️☀️🌧️
Use a public weather API to fetch real-time weather for a city. Great to explore APIs and the requests library.


For all resources and cheat sheets, check out my Telegram channel: https://t.me/pythonproz

Hope it helps :)

OnSpace Mobile App builder: Idea → AppStore → Profit.
👉https://onspace.ai/?via=tg_pg
With OnSpace, you can turn your idea into a real iOS or Android app in AppStore/PlayStore.

What will you get:
- Create app by chatting with AI
- Real-time app demo.
- Add payments and monetize like in-app-purchase and Stripe.
- Functional login & signup.
- Database + dashboard in minutes.
- Preview, download, and publish to AppStore.
- Full tutorial on YouTube and within 1 day customer service

🫵It’s your shortcut from concept to cash flow.

Top Coding Interview Questions 💻

📍 1. Two Sum Problem
Find two numbers in an array that add up to a target value.
Approach: Use a hash map to store complements for O(n) time.

📍 2. Reverse a Linked List
Reverse a singly linked list iteratively or recursively.

📍 3. Binary Tree Traversals
Implement Inorder, Preorder, and Postorder traversals (recursion or stack).

📍 4. Detect Cycle in a Linked List
Use Floyd’s Tortoise and Hare algorithm to detect if a loop exists.

📍 5. Merge Intervals
Given intervals, merge all overlapping intervals.

📍 6. Valid Parentheses
Use a stack to check for matching pairs of parentheses/brackets.

📍 7. Maximum Subarray Sum (Kadane’s Algorithm)
Find the contiguous subarray with the largest sum.

📍 8. Search in a Rotated Sorted Array
Modified binary search to find an element in a rotated sorted array.

📍 9. Implement Queue using Stacks
Use two stacks to simulate a queue’s FIFO behavior.

📍 🔟 Least Recently Used (LRU) Cache Implementation
Use a hashmap + doubly linked list for O(1) access and updates.

💡 Pro Tip: Master these core problems and practice explaining your thought process clearly. Also, get comfortable with coding on whiteboard or online editors.

10 Tools for Web Developers 🛠🚀 -

💻 Visual Studio Code - Lightweight code editor
🔍 Postman - API development and testing
🎨 CodePen - Front-end development playground
🐙 GitHub - Version control and collaboration
🎨 Figma - UI/UX design and prototyping
📊 Google Analytics - Website traffic analysis
🌐 Netlify - Easy web hosting and deployment
🔒 Auth0 - Authentication and authorization
📦 Webpack - Module bundler for modern JavaScript apps
📦 NPM - Node package manager for JavaScript libraries and tools

React ❤️ for more

💡 10 Habits That Will Make You a Better Programmer in 2025

1) Write code every day
Consistency builds confidence. Even 30 minutes daily makes a difference.

2) Read others' code
Study open-source projects or solutions on GitHub. You'll learn new patterns and cleaner ways to solve problems.

3) Break problems into smaller parts
Don't jump in. Outline the logic step-by-step. Simpler structure means fewer bugs.

4) Learn to debug efficiently
Use print statements, breakpoints, and logs. Understand what your code is doing, not what you think it's doing.

5) Focus on fundamentals
Data structures and algorithms never go out of style. Master them.

6) Use version control (Git)
Track changes, collaborate smoothly, and avoid "final_final_v2_updatedFIXED" files.

7) Write clean, readable code
Follow naming conventions. Use meaningful function names and comments only when necessary.

8) Build real-world projects
Apply what you learn. Build apps, bots, tools—anything that solves a real problem.

9) Stay curious
Tech moves fast. Subscribe to dev newsletters, follow GitHub repos, and try new tools.

10) Ask better questions
Whether you're Googling or posting on forums, be clear. Show your thought process and what you've tried.

💬 Double Tap ♥️ For More

𝗔𝗜/𝗠𝗟 𝗙𝗥𝗘𝗘 𝗢𝗻𝗹𝗶𝗻𝗲 𝗠𝗮𝘀𝘁𝗲𝗿𝗹𝗰𝗹𝗮𝘀𝘀😍

Kickstart Your AI & Machine Learning Career

- Leverage your skills in the AI-driven job market
- Get exposed to the Generative AI Tools, Technologies, and Platforms

Eligibility :- Working Professionals & Graduates 

𝗥𝗲𝗴𝗶𝘀𝘁𝗲𝗿 𝗙𝗼𝗿 𝗙𝗥𝗘𝗘👇:- 

https://pdlink.in/47fcsF5

Date :- October 30, 2025  Time:-7:00 PM

🧠 10 Mindset Shifts to Succeed in Programming & AI 🚀💻

1️⃣ Learn by Building
→ Don’t just watch tutorials—create projects, even small ones. Practice beats theory.

2️⃣ Fail Fast, Learn Faster
→ Bugs and errors are part of the process. Debugging teaches more than smooth runs.

3️⃣ Think in Systems, Not Scripts
→ Build reusable, modular systems instead of one-time scripts.

4️⃣ Start with Logic, Then Code
→ Don’t jump into code. Understand the logic, sketch it out first.

5️⃣ Embrace the AI Toolkit
→ Use tools like ChatGPT, Copilot, LangChain—they boost your output, not replace you.

6️⃣ Read Source Code
→ Understand how libraries and tools work internally—it sharpens your skills.

7️⃣ Communicate Clearly
→ Great programmers explain problems, solutions, and code simply—write clean code & good docs.

8️⃣ Consistency > Intensity
→ Daily learning or coding (even 30 mins) compounds over time.

9️⃣ Ask Better Questions
→ Whether in forums or AI prompts, clarity in your question leads to better answers.

🔟 Stay Curious, Stay Humble
→ Tech changes fast. Stay open to learning and unlearning.

💬 Double Tap ❤️ for more!