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A hospital tracks patient wait times in the emergency depart…

A hospital tracks patient wait times in the emergency department. Times are partitioned by day of the week and ordered by arrival time. If the hospital uses NTH_VALUE(wait_time, 3), what does the returned value represent? A) The third-longest wait time on that day B) The average of the first three wait times on that day C) The wait time of the third patient to arrive on that day D) The last patient’s wait time on that day Correct Answer: The wait time of the third patient to arrive on that day Explanation:Nth value returns the specified position within the ordered window. Since the data is ordered by arrival time, the third value corresponds to the third patient who arrived that day. It does not mean the third-longest time, an average, or the last patient’s wait time.

A regional manager ranks stores by sales in each city: SELE…

A regional manager ranks stores by sales in each city: SELECT city, store_id, SUM(sales) AS total_sales, RANK() OVER (PARTITION BY city ORDER BY SUM(sales) DESC) AS store_rank FROM stores GROUP BY city, store_id; If two stores tie for first place in a city, what will the next store’s rank be? OPTIONS:A. 2B. 3C. 1D. It depends on the number of total stores ANSWER:B EXPLANATION:RANK() skips numbers after ties (e.g., 1, 1, 3). To avoid skipped ranks, DENSE_RANK() would be used instead.

A sales manager wants to see how much each product contribut…

A sales manager wants to see how much each product contributes to total revenue: SELECT product_id, SUM(sales) AS product_sales, SUM(sales) OVER () AS total_sales FROM sales GROUP BY product_id; What does the total_sales column represent? OPTIONS:A. The total sales for each product onlyB. The total sales across all products, repeated for every rowC. The maximum sales of any productD. The running total of product sales in descending order ANSWER:B EXPLANATION:The empty OVER() applies the sum across the entire dataset, repeating the same total for each product.