Thursday, June 19, 2025

Free SQL Beginner & Interview Questions – A Curated Google Drive Resource

I’ve compiled a Google Drive folder full of SQL questions for beginners, along with a dedicated section for real SQL interview questions. These are collected from friends, personal experience, and different real-time interview situations.

🧠 The goal is simple: to provide a free, accessible resource to help students, job seekers, and anyone wanting to strengthen their SQL knowledge.

🔗 Access the Folder:
👉 https://drive.google.com/drive/folders/1YSrh3Vz5s44heAaWm_rhRsAvYlsxaRnC?usp=drive_link

📌 Note: This is a living resource — I will keep adding more updated or newly received question sheets in the same Drive folder as I receive them. So you can always visit again for fresh content.

You're welcome to:

  • Practice using the sheets

  • Share the link with learners or juniors

  • Suggest questions or feedback to improve the content

Let’s keep learning, growing, and helping each other 💪

— V MuraliDharan

Wednesday, June 4, 2025


 5 MySQL Tips That Can Save You Hours (From Real Experience)


Hello everyone! I'm Muralidharan, a database developer with 15+ years of hands-on experience. In this post, I’m sharing 5 MySQL tips that I’ve personally used many times — they’ve saved me hours of debugging and performance issues.

1. Use EXPLAIN Before You Optimize a Query

Always use EXPLAIN to analyze how MySQL executes your query. It shows whether indexes are used, and where performance bottlenecks may exist.

EXPLAIN SELECT * FROM customers WHERE city = 'Chennai';

2. Avoid SELECT * in Large Tables

Fetching all columns can slow down performance, especially if you only need a few. Always specify the required fields:

SELECT name, email FROM customers;

3. Use Proper Indexing

If you frequently use a column in WHERE, JOIN, or ORDER BY, make sure it's indexed. Example:

CREATE INDEX idx_city ON customers(city);

4. Watch for NULLs in Comparisons

Using = NULL won’t work. You must use IS NULL or IS NOT NULL to check for NULL values.

SELECT * FROM users WHERE email IS NULL;

5. Backup With mysqldump Regularly

Don’t rely only on GUI tools. Use the command line for fast, automated backups:

mysqldump -u root -p mydatabase > backup.sql

📌 Final Thought

If you're learning MySQL or working with real-time data, these tips will save you a lot of trouble. I’ll keep posting practical insights here.

Was this helpful? Comment below or email me at murali.pd@gmail.com with your questions or suggestions for the next post!

Until next time,
- Muralidharan V