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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What is a subquery?
💡 Hint: Think of it as a query within a query.
Question 2
Easy
Which clause often contains subqueries?
💡 Hint: It filters results based on criteria.
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 is a subquery?
- A standalone query
- A query within another query
- A join operation
💡 Hint: Think about how queries can be structured within one another.
Question 2
Do subqueries always perform better than JOINs?
- True
- False
💡 Hint: When do you think performance might be affected?
Solve 2 more questions and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
Construct a query to find product IDs for products that have been sold in orders totaling more than $500, using a subquery.
💡 Hint: Use SUM in the subquery to aggregate data.
Question 2
Write a SQL statement to find users who have not made any purchases. Use a subquery to achieve this.
💡 Hint: Think about how to filter users based on absence in the orders.
Challenge and get performance evaluation