Why does LAST_VALUE sometimes return the current row's value instead of the actual last value?

Because the default frame ends at the current row; you must specify ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING.

LAST_VALUE only works on primary keys.

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QUESTION 01 OF 02

Offset Functions

Quiz for lesson: Offset Functions

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What does LAG(revenue, 1) OVER (ORDER BY month) return?

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This interactive assessment is designed to test your understanding of Offset Functions. 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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