Window Functions Approach

Author

Andre Thomson

Approach

For this assignment, I will use a small generated dataset with daily values for two items. The dates will run from the end of 2025 into the beginning of 2026.

I will load the data into R and place it in a SQLite table. I will use SQL window functions to calculate the year-to-date average and the six-day moving average for each item. I will keep the items separate in the calculations so their values are not mixed together.

I will check the results around January 1 to confirm that the year-to-date average begins again for the new year. I will also check that each six-day average uses the current date and the previous five dates. I will show the results in a table and chart.

Data source

The assignment allows a generated dataset. The values in my file are examples and do not represent actual stock prices, sales, or workplace information.

References

CUNY School of Professional Studies. DATA 607 Assignment 3B: Window Functions Requirements. Brightspace course material, 2026.
SQLite. Window Functions. https://sqlite.org/windowfunctions.html