Seeking assistance with SQL query interview questions

Question

Hello,

I recently stumbled upon this SQL query interview questions tutorial. It offers a collection of SQL query problems to help practice and improve SQL skills for interviews. However, I'm facing some challenges while attempting to solve these questions and could use some guidance.

I've been working my way through the tutorial, but I've encountered a few questions where my queries are not producing the expected results. I've reviewed the solutions provided in the tutorial, but I'm still struggling to grasp the underlying concepts and apply them correctly.

To give you an idea of the problem I'm facing, here's an example of a question from the tutorial that has been giving me trouble:

      sql
-- My attempt at the problem
-- Insert your code here
 

I would greatly appreciate it if someone could provide some insights into the correct approach for solving these SQL query interview questions. If you've successfully solved similar SQL problems or have any tips or alternative approaches to share, please feel free to do so. Your guidance would help me better understand the concepts and improve my problem-solving skills.

Thank you all in advance.