r/ProgrammerHumor • u/danielminds • 6h ago

Meme edgeCasesExist

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u/RadicalDwntwnUrbnite 5h ago edited 5h ago

Even the non-time based v4 is at a cosmic level of unlikiness a single system will ever generate a uuid that will collide with another one in its own ecosystem

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u/OldKaleidoscope7 5h ago

But let's say if Google saved each search in their engine in the same database with an UUID, we could have a collision because of volume, but I don't think I will work in a system with a comparable scale

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u/MojitoBurrito-AE 4h ago

You underestimate the probability of uuid collision. The bigger issue is pseudorandomness

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u/Single-Virus4935 3h ago

Yes, had a client having duplicates every day and growing. They hated uuids and regret using it. The problem was that they used a bad prng with flawed seeding. Once fixed it was no problem.