📌 Introduction
Let’s be honest—SQL doesn’t sound as sexy as machine learning or AI. But guess what? I cracked my first job because I was good at writing clean, optimized SQL queries. And even now, in my 4th year in the industry, SQL is still my daily bread.
🧑💻 What Helped Me Stand Out in Interviews
- I could explain why I used
LEFT JOINoverINNER JOIN. - I understood window functions and could write queries using
ROW_NUMBER()to deduplicate data. - I always added a real-world use case when answering technical SQL questions.
💡 Example: Interview Question
Q: How would you get the 2nd highest salary in a table?
Most candidates blurt out subqueries. I said:
“In our payroll project, I once had to find the second-highest payout by department. I used
DENSE_RANK()over a partition by department_id and filtered where rank = 2.”
And that context is what impressed the panel.
🧠 Key Concepts Every Data Person Should Master in SQL
- Joins (not just syntax—real use cases)
- Aggregations and
GROUP BY - Window Functions
- CTEs and Subqueries
- Indexing and Query Optimization
✅ Final Tip
Don’t just write queries—explain them. Learn how your SQL logic solves business problems. That’s what hiring managers want.
