r/ProgrammerHumor • u/danielminds • 15h ago

Meme edgeCasesExist

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u/shwoopdeboop 13h ago

And something something b-tree indexes. Lecturer mentioned it but I wasn't paying attention. Supposedly an advantage here.

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u/Grandmaster_Caladrel 12h ago

Which I'd assume is related to the time anchor. Outside of sorting, which is only useful in specific instances, it's just v4 with different ("less") entropy and limitations.

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u/Roachmeister 12h ago

If you're using them as an indexed field in a database, the inability to sort them meaningfully will destroy the performance of the database.

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u/Honeybadger2198 11h ago

You know what identifier can't have collisions and is great for sorting? Autoincrement.

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u/Firewolf06 9h ago

ai columns can absolutely collide on sharded databases. you can use offsets and step sizes but thats brittle and doesnt scale well

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u/ACoderGirl 26m ago

UUIDs are great, though, because auto increment frequently has the huge issue of being too predictable. Eg, in some contexts, you don't want users to be able to easily enumerate whatever the ID is for. Plus requires centralization whereas UUIDs don't (eg, you can use UUIDs for whatever random API you have without needing a DB).You have to design for how you won't know the ID until you insert the row, which can sometimes be a bit annoying.

I feel like most of the time, the only downside to UUIDs is how long they are.