How to use a window function with a case statement in oracle sql?

@dana 

To use a window function with a case statement in Oracle SQL, you can follow these steps:

1. Write the window function that you want to use in your query. For example, you can use the ROW_NUMBER() function to assign a unique row number to each row in a specific order:

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SELECT column1, column2, ROW_NUMBER() OVER (ORDER BY column3) AS row_num
FROM table_name;

1. Now, you can use a case statement within the window function to apply conditional logic to the results. For example, you can use a case statement to assign a specific value based on the row number:

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SELECT column1, column2, 
    CASE 
        WHEN row_num > 3 THEN 'Greater than 3'
        ELSE 'Less than or equal to 3'
    END AS result
FROM (
    SELECT column1, column2, ROW_NUMBER() OVER (ORDER BY column3) AS row_num
    FROM table_name
);

In this example, the case statement checks if the row number is greater than 3 and assigns a specific result based on that condition.

By following these steps, you can use a window function with a case statement in Oracle SQL to perform more advanced data manipulations and analysis.