Let’s practice querying JSON columns while it’s still fresh in our memories. We’re running ahead of schedule with learning about AB-test, but why not? It’s a perfect example
Brief recap: AB-testing is a tool to optimize performance of … basically anything. We split website visitors into couple of groups. One group has treatment A, the other – treatment B. Later we compare performance (signup rate, purchase rate, ARPU etc) of both groups and keep the winning variation on the website for all future visitors. We can AB-test not just website, but...