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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What is the purpose of a subquery in SQL?
💡 Hint: Think about how one query can feed into another.
Question 2
Easy
Can subqueries be used in the WHERE clause?
💡 Hint: Consider how we restrict results based on another dataset.
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 query that joins tables
- A query within another query
- A query that deletes data
💡 Hint: Recall how one query can influence another.
Question 2
Subqueries can be used in which SQL clauses?
- SELECT
- WHERE
- FROM
- All of the above
💡 Hint: Think of all the places we've mentioned using them.
Solve 2 more questions and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
Create a SQL query that retrieves the names of employees who earn more than the average salary of their specific department, using subqueries.
💡 Hint: Think about how to correlate the subquery with the outer query logically.
Question 2
Explain under what circumstances you would prefer using a JOIN over a subquery and provide an example.
💡 Hint: Consider the relationships between tables and how to express them directly.
Challenge and get performance evaluation