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A comment on Things you should do now (2011). Parent comment

Re:Things you should do now (2011) by marcus_holmes on Friday February 19, 2021 @09:12AM (#26193315)
this, also there's no possibility of collision. You can't have two processes generate the same ID (which means you can generate your IDs in code and send them to the database, which is really useful in some situations).

Also, and this is the main one for me - if I mess up my code and accidentally use a document_id instead of a user_id, I'll just get "not found" instead of someone else's data.

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Re:Things you should do now (2011) by mherrmann on Friday February 19, 2021 @09:31AM (#26193516)
Actually, afaik uuids are pseudo-random and can thus absolutely collide in theory. Collision is solved by every db backend out there.
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Re:Things you should do now (2011) by marcus_holmes on Friday February 19, 2021 @10:22AM (#26194093)
UUID collision is not possible in practice. You can absolutely code in the absolute knowledge that your application will not generate 2 identical UUID's ever. The odds are astronomical. You have bigger concerns.

And yes, every DB backend has solved collision. But as I said, it's useful to be able to generate ID's in code sometimes. This is possible with UUID's and not possible with integers.

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Re:Things you should do now (2011) by marcosdumay on Friday February 19, 2021 @02:18PM (#26196848)
> UUID collision is not possible in practice.

UUID is a loosely defined concept. There are many implementations. Some of them have no chance of collision at all, some have an astronomical chance, and some have very real odds that you'll receive a call at 3AM during the new year's celebration.

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Re:Things you should do now (2011) by deckard1 on Friday February 19, 2021 @07:07PM (#26199774)
just make sure you have everything configured correctly on your system if using UUIDs:

https://github.com/ramsey/uuid/issues/80

In the types of systems that need UUIDs there is probably no easy way to check for collisions. The prospect of mystery data corruption with no ability to trace it down frightens the hell out of me.

The only reason that issue was reported is because someone was actually doing the collision checking. That's not going to be the norm in UUID systems. Think about it.

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Re:Things you should do now (2011) by derwiki on Friday February 19, 2021 @09:48AM (#26193696)
Many shops (I presume, since I work at non-FAANG) have their own version of UUID generation that includes info about the machine/instance it was generated from. I don’t think we’ve formally proved it but I think ours is guaranteed unique in our fleet.
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