-Pareto Principle (80-20 Rule) Implementation in SQL||SQL INTREVIEW QUESTION

---------------Pareto Principle (80-20 Rule) Implementation in SQL--------------------------------

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with CTE1 as
(
select SSO.Product_ID,SUM (SSO.Sales) as 'Product Sales' FROM  [dbo].[Sample - Superstore_Orders] SSO GROUP BY SSO.Product_ID
),Sales_cal as
(
select Product_ID,Sales,sum (Sales) over (ORDER BY Sales DESC ROWS BETWEEN UNBOUNDED PRECEDING AND 0 PRECEDING ) as 'Running Sales',SUM (Sales) OVER ()* 0.8 as"Total Sales" FROM 
[dbo].[Sample - Superstore_Orders]
)
select * from Sales_cal WHERE Sales_cal.[Running Sales] <=Sales_cal.[Total Sales]

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