Window (or analytic) functions are an essential part of SQL. Using them you can calculate running totals, moving averages, and get values from other rows.

But how exactly do they work?

This session uses Oracle Analytics Cloud to show you which rows are included in the calculation for different OVER clauses

Highlights include:

02:30 - What the OVER clause does
03:00 - The WINDOWS clause
03:45 - The PARTITION BY clause
06:00 - The ORDER BY clause
09:15 - Define a sliding window with ORDER BY 1 PRECEDING AND 1 FOLLOWING
15:20 - Remove rows from the window with EXCLUDE
20:50 - Combining PARTITION BY with ORDER BY
26:30 - Get values from the previous or next rows with LAG/LEAD
33:30 - How sorting using non-unique values affects the results
37:30 - Using window functions to avoid self-joins
40:00 - Using window functions to calculate running totals or moving averages
41:15 - Using window functions to do inter-row calculations
43:00 - Example query to avoid repeated table access
46:00 - Recap
49:30 - Using RANK/ROW_NUMBER/DENSE_RANK with PARTITION BY

Learn about SQL window function for free on Oracle Dev Gym https://devgym.oracle.com/pls/apex/dg/class/analytic-sql-for-developers.html