LeetCode Database Solutions [Easy] 003 | Eugene Tsai

photo by Christin Hume

Introduction

This is the third article about the easy level database solutions on LeetCode. Just a kindly reminder that if you are a new reader here, I am writing this article not only for my personal future review, but also for people who are practicing SQL queries, or deciding to pursue a career in analytic fields. This is a serial article, so for those who have not seen the first and second articles, the links below are the right place for you. If you think this article is supportive, do not forget to follow me, and click a clap for me!

LeetCode Database Solutions [Easy] 001 | Eugene Tsai

LeetCode Database Solutions [Easy] 002 | Eugene Tsai

LeetCode Database Solutions [Easy] 004 | Eugene Tsai

LeetCode Database Solutions [Easy] 005 | Eugene Tsai

LeetCode Database Questions

1. No 511. Game Analysis I
2. No 584. Find Customer Referee
3. No 586. Customer Placing the Largest Number of Orders

Let’s go

No 511. Game Analysis I

Table: Activity

Question:

MySQL Solutions:

Approach I:

Approach II:

No 584. Find Customer Referee

Table: Customer

Question:

MySQL Solutions:

Approach I:

Approach II:

No 586. Customer Placing the Largest Number of Orders

Table: Orders

Question:

MySQL Solutions:

Approach I:

Approach II:

Conclusion

Let’s call it a day. Here are the solutions of the three easy level database questions on LeetCode. If you think this article is helpful, do not hesitate to follow me, and click a clap for me. Moreover, if you can come up with better or more efficient solutions, always be free to have a discussion with me, or connect me on my LinkedIn. Thank you for time!