Question 1

What is a UUID?

Accepted Answer

A UUID is a 128-bit identifier written as 36 characters with dashes. It is effectively unique, so it works as a record key without a central counter.

Question 2

How does UUID v4 differ from v7?

Accepted Answer

Version 4 is fully random. Version 7 embeds a timestamp at the start, so the identifiers sort chronologically and behave better as database keys.

Question 3

Can two generated UUIDs collide?

Accepted Answer

In practice, no. The value space is so large that a collision is extremely unlikely even across billions of identifiers.

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UUID generator