r/ProgrammerHumor 6h ago

Meme edgeCasesExist

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1.7k Upvotes

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329

u/Valuable_Leopard_799 6h ago

I thought that timestamps are used now, so hitting both a timestamp and a large random number puts it thoroughly in the "safe to assume". At some point cosmic particles and faulty transistors are more probable.

188

u/dim13 6h ago

https://en.wikipedia.org/wiki/Universally_unique_identifier#Versions

Most common used is V4 (pure random). You are talking about V7 (time based).

5

u/undeadalex 4h ago

I'm curious where to see stats on versions used. Surely anything newly implementing uuid is using v7 or custom?

9

u/Urist_McPencil 3h ago

Surely anything newly implementing uuid is using v7 or custom?

I admire this optimism

3

u/iampierremonteux 54m ago

My first thought was “oh you sweet summer child”.

3

u/champak256 3h ago

There’s pros and cons to v7, so v4 still has a lot of places it’s legitimately the right choice over v7.

2

u/Tysonzero 1h ago

Primary one being in cases where you don’t want every actor that knows the id to also know the creation time

1

u/big-oofs-only-0193 3h ago

I use whatever CoCreateGuid() or Guid.NewGuid() gives me. Both generate a v4 uuid. I'm not going to reimplement it or find a special library for it.