Window functions
SQL window functions explained
Window functions let you calculate rankings, comparisons, and running totals across a set of rows while keeping the underlying row structure visible.
Common analytical patterns
PARTITION BY
Break calculations into logical groups such as customers, regions, or product categories.
ORDER BY
Define the sequence used to rank rows or calculate running totals.
ROW_NUMBER
Assign a unique number to each row even when values are tied.
RANK and DENSE_RANK
Rank rows while handling ties in different ways.
Running totals
Calculate cumulative totals across ordered rows in a practical reporting workflow.
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