Scenario

Given a large volume of data, we want to determine the average of a certain field, grouped by some other field.

This is a very simple exercise, and it probably does not constitute a pattern, but it does provide a useful introduction to PhixFlow and the aggregate functions built into the pipe functionality.

Solution:

1. Create a table (loaded from a file is fine) containing a list of countries, years and populations.
2. Create second table from the data in the first table.
3. Configure the pipe that joins the 2 tables to calculate the average population, grouped by country.