🌟 Dreaming of a bright future? 🎓 Ask about the Treehouse Scholarship program! 🚀
✨ Earn college credits in Cybersecurity, JS, HTML, CSS and Python
Take our "AI in Tech Jobs" survey and win 3 months free Treehouse!
New No-Code Track! 🚀 New videos dropping every week—start learning today!
🤑 Join the Treehouse affiliate program and earn 25% commission!
A Primary Key will allow one NULL value, but no more than that.
Choose the correct answer below:
There was an error while reporting the question. Please try again, or contact support directly.
Describe the issue (optional) (required)
Your feedback has been submitted. Thank you!
If you continue experiencing problems, please contact support at help@teamtreehouse.com.
Quizzes are the best way to test your knowlege. Sign up for Treehouse today and prove yourself. We guarantee 100% satisfaction.