[fathomdeez]

I don't think of those as business logic, per se. They're just validity checks on what the data should look like before it's written to disk - they're not actionable in the way L/N is. That being said, constraints usually end up being duplicated outside the db anyway, but having them where the data rests (so you don't have to assume every client is using the correct constraint code) makes sense.

[panzi]

I see. Further I have used triggers to automatically populate log tables or aggregate statistics on write. Why do I need fast statistics? For API limits. Customers have N free operations per months and such, so I have to query that on every operation. Do you consider these things as business logic that don't belong in the database?