follows is a graph stored as a table: each row is an edge from follower to followee.

1. List the people that Ava's followees follow: two steps from ava. One column, each name once.
2. A query for the people exactly 5 steps from Ava: how many copies of follows does it need in the FROM?

Choose the model for each workload: relational, document, key-value, wide-column or graph.

3. A bank ledger: transfers between accounts, with strict rules on every balance.
4. Shopping-cart sessions, read and written by session id, deleted after one hour.
5. A product catalogue: a guitar, a T-shirt and a laptop each have different attributes, and the app reads one whole product at a time.
6. "People you may know": people three steps away in a network of 50 million users.
7. Temperature readings from a million sensors, every second, read by sensor and time range.