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question, possible uuid collision

See original GitHub issue

Hi, I’ve seen some projects doing this with this package: v4().substr(0, 10) to only take the 10 first characters of the UUID.

Is this creating a risk of collision ?

Issue Analytics

State:
Created 3 years ago
Comments:9 (6 by maintainers)

Top GitHub Comments

1reaction

broofacommented, Apr 22, 2020

At the risk of being pedantic, a “10 char UUID” is an oxymoron. “UUID” has a very specific definition (see RFC 4122). tl;dr - they are 128-bit values that, when formatted as strings, have 32 hex characters and four ‘-’ chars.

There are many libraries out there for generating unique IDs of various flavors. E.g. nanoid and shortid. Just be aware that you’re venturing into “non-standard” territory and don’t expect such IDs to play nice in contexts (like databases) that have built-in support for UUIDs.

1reaction

LinusUcommented, Apr 22, 2020

Yes.

You are only getting 9 hexadecimal characters of randomness (9 because one of the 10 will always be -)

ref: https://zelark.github.io/nano-id-cc/

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