Comment by remixff2400

Spinning up DB instances is a lot faster now than it used to be in the past. There are even modules for in-memory instances of certain databases. The speed of a unit test vs. that of one that uses an actual database is small enough for it to be a real consideration.

That being said, of course, "it depends" on your use case. But I've found setting up this sort of test environment quite a bit easier now than writing database mocks, a lot less time-and-maintenance intensive, and relatively quick to run in any environment.

(Also, in a decade, I'm pretty confident this gap will get even smaller, while the time to maintain mocks will stay constant)