Country Codes is one of the five questions in the HackerRank SQL (Basic) certification test. The join is simple. Most people who fail it get the string joining wrong, because MySQL handles it ...

This is one of the questions in the HackerRank SQL (Intermediate) certification test. It was one of the two I got when I took the test in June 2022. The query below is tested on MySQL 8.0 and 5.7.

For over 5 years, Arthur has been professionally covering video games, writing guides and walkthroughs. His passion for video games began at age 10 in 2010 when he first played Gothic, an immersive ...