Last tested: April 2021
How do I use window functions in Looker?
Window functions are a very powerful tool in SQL because they perform post-aggregation calculations. There are two main ways to implement window functions in Looker:
1: Use Table Calculations
Calculating after aggregations is exactly what table calculations excel at. Many common window functions in SQL can be replaced by table calcs like
offset, or clever combinations thereof. Do keep in mind though, table calculations can only be performed on the data within the Data Tab of the Explore page!
2: Use a derived table
If table calculations don't provide what you need, you can always write a derived table with whatever SQL you want, including window functions.