> Retrieving data from the database is an incoming interaction — it doesn’t result in a side effect. Unless you count the time taken to retrieve the data as a

> Retrieving data from the database is an incoming interaction — it doesn’t result in a side effect. Unless you count the time taken to retrieve the data as a side effect. If you are implementing a cache with a well specified behavior then you might want to test incoming interactions. Anyway, this just shows that having a side effect can be a matter of perspective.