Practice relationship aggregation

In the previous lesson, you learned the theory behind relationship aggregationCollapsing the parallel relationships between two nodes into one during projection, usually carrying their count or sum as its weight.. Now you'll practice building aggregated projectionsAn in-memory copy of part of your database that graph algorithms run against. You choose which nodes and relationships it holds. using count(r) to count relationshipsA named, directed connection between two nodes. Every relationship has a type, a start node and an end node. between nodeA vertex in a graph. In a property graph it can carry labels and properties. pairs.

Here's how it's done: