Advanced Analytical Window Functions (OVER, ROW_NUMBER, PARTITION BY)
Compute running totals, moving averages, and ranks across row partitions using OVER(PARTITION BY ... ORDER BY ...) without collapsing rows.
Window Functions vs GROUP BY
### Window Functions
Unlike `GROUP BY` which collapses grouped rows into a single summary output line, **Window Functions** compute aggregate values across a partition of rows while retaining individual row identities.
