ORM: when to raise an exception: on object creation or on use?

Less exception handling. Exception handling is invented to reduce the amount of code handling exceptional situations.
In general, you are raising a big topic. There is some big misconception that programming should be defensive. People think so because, for example, this is what they were taught at school. But development of relational model, SQL and exception handling demonstrates that programming can be and often should be offensive. It's stupid to checkup if the file exists. Instead, you can just use the file via, say, StreamReader and face exception when it fails. It's even deeper in SQL. Instead of checking that something exists, it's better to find it by a single query. And so on...

Now, there is a lot of heated discussions against ORM, which is considered as anti-patten itself. I don't have a certain opinion on this topic, but some of the arguments blame it or being offensive. Like in the known meme: "You make that sound like a bad thing".

Doing things later makes programming more offensive, and I think it's generally good.

I don't want to publish a formal answer, because the issue is deep and ambiguous. It's just some food for thought.

—SA

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