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Comment by 9rx | Hacker News Reader

> and your app doesn't have 300% test coverage with fuzzing like SQLite does

Surely it does? Otherwise you cannot trust the interface point with SQLite and you're no further ahead. SQLite being flawless doesn't mean much if you screw things up before getting to it.

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That's true but relying on a highly tested component like SQLite means that you can focus your tests on the interface and your business logic, i.e. you can test that you are persisting to the your datastore rather than testing that your datastore implementation is valid.

Your business logic tests will already, by osmosis, exercise the backing data store in every conceivable way to the fundamental extent that is possible with testing given finite time. If that's not the case, your business logic tests have cases that have been overlooked. Choosing SQLite does mean that it will also be tested for code paths that your application will never touch, but who cares about that? It makes no difference if code that is never executed is theoretically buggy.

Business logic tests will rarely test what happens to your data if a machine loses power.

Then your business logic contains unspecified behaviour. Maybe you have a business situation where power loss conditions being unspecified is perfectly acceptable, but if that is so it doesn't really matter what happens to your backing data store either.

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