Please can I have the solution to this problem?

Exercise 25.4 Briefly answer the following questions: 1. What is the difIerences between the WINDOW clause and the GROUP BY clause'? 2. Give an example query that cannot be expressed in SQL without the WINDOW clause but that can be expressed with the WINDOW clause. :3. What is the fTCLrne of a window in SQL:19997 4. Consider the fonowing simple GROUP BY query. SELECT FROM WHERE GROUP BY T.year, SUM (S.sales) Sales 5, Tilnes T S.tilneid='T.timeid T.year Can you write this query in SQL:1999 without using a GROUP BY cIa.use? (Hint: Use the SQL:1999 WINDOW clause.)

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