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Questions tagged [guid]

A GUID (Globally Unique IDentifier) is a unique reference number used as an identifier in computer software.

A GUID (Globally Unique IDentifier) is a unique reference number used as an identifier in computer software. It is Microsoft's implementation of the UUID standard.

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How to create a GUID / UUID

I'm trying to create globally-unique identifiers in JavaScript. I'm not sure what routines are available on all browsers, how "random" and seeded the built-in random number generator is, etc. The GUID / UUID should be at least 32 characters and…
Jason Cohen
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Is there any difference between a GUID and a UUID?

I see these 2 acronyms thrown around, and I was wondering if there are any differences between a GUID and a UUID?
Jon Tackabury
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How to create a GUID/UUID in Python

How do I create a GUID in Python that is platform independent? I hear there is a method using ActivePython on Windows but it's Windows only because it uses COM. Is there a method using plain Python?
Jonathon Watney
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Is a GUID unique 100% of the time?

Is a GUID unique 100% of the time? Will it stay unique over multiple threads?
David Basarab
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C# how to create a Guid value?

One field of our struct is Guid type. How to generate a valid value for it?
5YrsLaterDBA
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How unique is UUID?

How safe is it to use UUID to uniquely identify something (I'm using it for files uploaded to the server)? As I understand it, it is based off random numbers. However, it seems to me that given enough time, it would eventually repeat it self, just…
Jason
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What is the string length of a GUID?

I want to create a varchar column in SQL that should contain N'guid' while guid is a generated GUID by .NET (Guid.NewGuid) - class System.Guid. What is the length of the varchar I should expect from a GUID? Is it a static length? Should I use…
Shimmy Weitzhandler
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Create a GUID in Java

What are some of the best ways to create a GUID in Java?
Chris Dutrow
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Guid.NewGuid() vs. new Guid()

What's the difference between Guid.NewGuid() and new Guid()? Which one is preferred?
OscarRyz
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What are the best practices for using a GUID as a primary key, specifically regarding performance?

I have an application that uses GUID as the Primary Key in almost all tables and I have read that there are issues about performance when using GUID as Primary Key. Honestly, I haven't seen any problem, but I'm about to start a new application and I…
VAAA
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How to test valid UUID/GUID?

How to check if variable contains valid UUID/GUID identifier? I'm currently interested only in validating types 1 and 4, but it should not be a limitation to your answers.
Marek Sebera
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Simple proof that GUID is not unique

I'd like to prove that a GUID is not unique in a simple test program. I expected the following code to run for hours, but it's not working. How can I make it work? BigInteger begin = new BigInteger((long)0); BigInteger end = new…
Kai
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Generate a UUID on iOS from Swift

In my iOS Swift app I want to generate random UUID (GUID) strings for use as a table key, and this snippet appears to work: let uuid = CFUUIDCreateString(nil, CFUUIDCreate(nil)) Is this safe? Or is there perhaps a better (recommended) approach?
zacjordaan
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Guid is all 0's (zeros)?

I'm testing out some WCF services that send objects with Guids back and forth. In my web app test code, I'm doing the following: var responseObject = proxy.CallService(new RequestObject { Data = "misc. data", Guid = new Guid() }); For some…
Didaxis
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Advantages and disadvantages of GUID / UUID database keys

I've worked on a number of database systems in the past where moving entries between databases would have been made a lot easier if all the database keys had been GUID / UUID values. I've considered going down this path a few times, but there's…
Matt Sheppard
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