advantage of using Window functions over regular aggregate functions is: Window functions do not cause rows to become grouped into a single output row, the rows retain their separate identities and an aggregated value will be added to each row

Types of Window functions
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1. Aggregate Window Functions
        SUM(), MAX(), MIN(), AVG(). COUNT()
2. Ranking Window Functions
        RANK(), DENSE_RANK(), ROW_NUMBER(), NTILE()
3. Value Window Functions
        LAG(), LEAD(), FIRST_VALUE(), LAST_VALUE()