Currently, UUID’s are as specified in RFC4122. An often neglected edge case is the NIL UUID, noted here. The following regex takes this into account and will return a match for a NIL UUID. See below for a UUID which only accepts non-NIL UUIDs. Both of these solutions are for versions 1 to 5 (see the … Read more
GUID technically stands for globally unique identifier. What it is, actually, is a 128 bit structure that is unlikely to ever repeat or create a collision. If you do the maths, the domain of values is in the undecillions. Use guids when you have multiple independent systems or clients generating ID’s that need to be unique. For example, … Read more
UUIDs (Universally Unique IDentifier), also known as GUIDs (Globally Unique IDentifier), according to RFC 4122, are identifiers designed to provide certain uniqueness guarantees. While it is possible to implement RFC-compliant UUIDs in a few lines of JavaScript code (e.g., see @broofa’s answer, below) there are several common pitfalls: Invalid id format (UUIDs must be of the form … Read more
The uuid module provides immutable UUID objects (the UUID class) and the functions uuid1(), uuid3(), uuid4(), uuid5() for generating version 1, 3, 4, and 5 UUIDs as specified in RFC 4122. If all you want is a unique ID, you should probably call uuid1() or uuid4(). Note that uuid1() may compromise privacy since it creates a UUID containing … Read more