Day 1: Learning SQL to Get Hired

Welcome to Day 1 of my "Learning SQL to Get Hired" series!

Today, I’m tackling FOUR LeetCode SQL problems to build foundational skills:
- #584 Find Customer Referee
- #595 Big Countries
- #1148 Article Views I
- #1683 Invalid Tweets

What you'll learn:
- Writing simple SELECT + WHERE queries
- Handling NULLs and filtering data
- Real-world patterns you’ll see in interviews and system engineering jobs

I’m walking through my thought process, not just dumping solutions, including how I debug mistakes and what I’d expect if asked this in a Microsoft or data-focused interview. Try these on your own, then share how you approached them!

Problem links:
https://leetcode.com/problems/find-customer-referee/
https://leetcode.com/problems/big-countries/
https://leetcode.com/problems/article-views-i/
https://leetcode.com/problems/invalid-tweets/

Timestamps:
0:00 - Introduction
0:55 - Find Customer Referee
5:16 - Big Countries
9:10 - Article Views I
24:24 - Invalid Tweets
27:09 - Conclusion

Видео Day 1: Learning SQL to Get Hired канала Nicholas Facciola