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I’ve never seen anything remotely like that in a schema and it seems inappropriate anyway - those should IMO be timestamps like saw_eclipse_at not booleans. You should not encode business rules in the schema (like certain magic dates) because those business rules always change over time.

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Yeah, need a bit of imagination to walk there with me, but you are saying just use `saw_eclipse_at`. That would require having knowledge of the entity's birthday, the date that the event occurred on, and so on, which in this imaginary scenario, we do not.

I would not store that in a schema, storing bday and date seen is much more useful so that when the business inevitably asks for saw eclipse at 50 too you can answer the question without adding a saw at 50 boolean. Bday is also super useful info for a business that cares how old someone is (as your hypothetical one clearly does).

Often the stated requirements of a problem are far too specific. Part of the job is system design is saying no to suggestions and finding the deeper constraints.

This example is a great illustration of why booleans are usually a mistake.

> This example is a great illustration of why booleans are usually a mistake.

It is not. You are ignoring hypothetical constraints to bolster your own hypothetical argument, which is apparently some permutation of, "tell people they are wrong, and do some imputing of imaginary data. repeat until you have ideal 'system design'"

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