Professional Courses
Industry-relevant training in Business, Technology, and Design to help professionals and graduates upskill for real-world careers.
Categories
Interactive Games
Fun, engaging games to boost memory, math fluency, typing speed, and English skills—perfect for learners of all ages.
Typing
Memory
Math
English Adventures
Knowledge
Enroll to start learning
You’ve not yet enrolled in this course. Please enroll for free to listen to audio lessons, classroom podcasts and take practice test.
Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What does an INNER JOIN do?
💡 Hint: Think about how it filters records.
Question 2
Easy
Explain what a LEFT JOIN does.
💡 Hint: Remember, unmatched records from the right will show NULLs.
Practice 4 more questions and get performance evaluation
Interactive Quizzes
Engage in quick quizzes to reinforce what you've learned and check your comprehension.
Question 1
What type of join returns records with matching values in both tables?
- INNER JOIN
- LEFT JOIN
- RIGHT JOIN
💡 Hint: Focus on matching values.
Question 2
True or False: A LEFT JOIN will always return rows even if there are no matches in the right table.
- True
- False
💡 Hint: Consider what happens to unmatched records.
Solve 1 more question and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
Given two tables: 'students' (id, name) and 'enrollments' (student_id, course_id), write a query using LEFT JOIN to select all students and their enrolled courses. Include students not enrolled in any course.
💡 Hint: Remember to include all students, regardless of their enrollment status.
Question 2
Using RIGHT JOIN, write a query to find all courses and the students enrolled in them, including courses with no students enrolled.
💡 Hint: Focus on ensuring all courses are listed.
Challenge and get performance evaluation