1. What is returned by AVG(rating) on a table of 5 reviews with ratings: 5, 4, NULL, 3, NULL?
- 2.4 (total divided by 5)
- 4 (total divided by 3)
- NULL
- An error
Hint: AVG ignores NULLs. The sum is 12 (5+4+3) and the count is 3. 12 / 3 = 4.
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QUESTION 01 OF 02
Aggregates and NULL values
Quiz for lesson: Aggregates and NULL values
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What is returned by AVG(rating) on a table of 5 reviews with ratings: 5, 4, NULL, 3, NULL?
About this Quiz
This interactive assessment is designed to test your understanding of Aggregates and NULL values. Whether you are a beginner looking to grasp the basics or an experienced professional aiming to refine your skills, quizzes are an excellent way to validate your knowledge and identify areas for improvement.
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Learning Outcomes
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- Reinforce key concepts through active recall.
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