Questions tagged [guid]
A GUID (Globally Unique IDentifier) is a unique reference number used as an identifier in computer software.
guid
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How do I create a GUID / UUID?
How do I create GUIDs (globally-unique identifiers) in JavaScript? The GUID / UUID should be at least 32 characters and should stay in the ASCII range to avoid trouble when passing them around.
I'm ...
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How to create a GUID/UUID in Python
How do I create a GUID/UUID 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 ...
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Is there any difference between a GUID and a UUID?
I see these two acronyms being thrown around and I was wondering if there are any differences between a GUID and a UUID?
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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 ...
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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?
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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?
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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 ...
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What are the best practices for using a GUID as a primary key, specifically regarding performance? [closed]
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 ...
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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.
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Guid.NewGuid() vs. new Guid()
What's the difference between Guid.NewGuid() and new Guid()?
Which one is preferred?
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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 ...
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Simple proof that GUID is not unique [closed]
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((...
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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 = "...
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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 ...
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How to create a GUID/UUID using iOS
I want to be able to create a GUID/UUID on the iPhone and iPad.
The intention is to be able to create keys for distributed data that are all unique. Is there a way to do this with the iOS SDK?
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SQL Server: converting UniqueIdentifier to string in a case statement
We have a log table that has a message column that sometimes has an exception stack trace. I have some criteria that determines if the message has this. We do not want to show these messages to the ...
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Test if string is a guid without throwing exceptions?
I want to try to convert a string to a Guid, but I don't want to rely on catching exceptions (
for performance reasons - exceptions are expensive
for usability reasons - the debugger pops up
for ...
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How to validate GUID is a GUID
How to determine if a string contains a GUID vs just a string of numbers.
will a GUID always contain at least 1 alpha character?
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What is the default value for Guid?
The default value for int is 0 , for string is "" and for boolean it is false. Could someone please clarify what the default value for guid is?
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How should I store GUID in MySQL tables?
Do I use varchar(36) or are there any better ways to do it?
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Best way to create unique token in Rails?
Here's what I'm using. The token doesn't necessarily have to be heard to guess, it's more like a short url identifier than anything else, and I want to keep it short. I've followed some examples I've ...
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Generating GUIDs in Ruby
I have a problem that is really easily solved with GUIDs.
In particular, for a password reset workflow, I would like to send a GUID token to a user's email and have them reset their password using the ...
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Are GUID collisions possible?
I'm working on a database in SQL Server 2000 that uses a GUID for each user that uses the app it's tied to. Somehow, two users ended up with the same GUID. I know that microsoft uses an algorithm to ...
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Is it safe to assume a GUID will always be unique?
I know there is a minute possibility of a clash but if I generated a batch of 1000 GUIDs (for example), would it be safe to assume they're all unique to save testing each one?
Bonus question
An ...
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Generate GUID in MySQL for existing Data?
I've just imported a bunch of data to a MySQL table and I have a column "GUID" that I want to basically fill down all existing rows with new and unique random GUID's.
How do I do this in MySQL ?
I ...
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How to Create Deterministic Guids
In our application we are creating Xml files with an attribute that has a Guid value. This value needed to be consistent between file upgrades. So even if everything else in the file changes, the guid ...
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How to generate a GUID in Oracle?
Is it possible to auto-generate a GUID into an Insert statement?
Also, what type of field should I use to store this GUID?
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I need to generate uuid for my rails application. What are the options(gems) I have? [duplicate]
I use
Rails 3.0.20 and
ruby 1.8.7 (2011-06-30 patchlevel 352)
Please suggest me the best plugin to generate guid.
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How to generate short uid like "aX4j9Z" (in JS)
For my web application (in JavaScript) I want to generate short guids (for different objects - that are actually different types - strings and arrays of strings)
I want something like "aX4j9Z" for my ...
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UUID format: 8-4-4-4-12 - Why?
Why are UUID's presented in the format "8-4-4-4-12" (digits)? I've had a look around for the reason but can't find the decision that calls for it.
Example of UUID formatted as hex string:
58D5E212-...
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SCOPE_IDENTITY() for GUIDs?
Can anyone tell me if there is an equivalent of SCOPE_IDENTITY() when using GUIDs as a primary key in SQL Server?
I don't want to create the GUID first and save as a variable as we're using ...
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What is {{$guid}} used for in Postman?
Postman's official website states that Postman has a few dynamic variables. My question is about:
{{$guid}}: Adds a v4 style guid
What kind of variable is {{$guid}}? How can it be used in test ...
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guid/uuid in Typescript Node.js app
I try to make a uuid (v 3.0.1) package work in Node/Typescript app, but I'm not sure what should I import and how to use it.
This is index.d.ts (from @types/uuid v 2.0.29):
declare namespace uuid {
...
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Guid.Parse() or new Guid() - What's the difference?
What is the difference between these two ways of converting a string to System.Guid? Is there a reason to choose one over the other?
var myguid = Guid.Parse("9546482E-887A-4CAB-A403-AD9C326FFDA5");
...
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What exactly is GUID? Why and where I should use it?
What exactly is GUID? Why and where I should use it?
I've seen references to GUID in a lot of places, and in wikipedia,
but it is not very clear telling you where to use it.
If someone could answer ...
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How to convert a GUID to a string in C#?
I'm new to C#.
I know in vb.net, i can do this:
Dim guid as string = System.Guid.NewGuid.ToString
In C#, I'm trying to do
String guid = System.Guid.NewGuid().ToString;
but i get an "Cannot ...
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A TypeScript GUID class? [closed]
Does anyone know of a good, solid, implementation of C# like GUID (UUID) in TypeScript?
Could do it myself but figured I'd spare my time if someone else done it before.
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How many characters are there in a GUID?
Using ASCII encoding, how many characters are there in a GUID?
I'm interested in the Microsoft style, which includes the curly brackets and dashes.
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What are the project GUIDs in a Visual Studio solution file used for?
I have multiple projects in a single Visual Studio (2008) solution.
I just discovered that each of these projects uses a same GUID, so in the solution file it looks like this:
Project("{FAE04EC0-F103-...
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How unique is the php session id
How unique is the php session id? I got the impression from various things that I've read that I should not rely on two users never getting the same sessionid. Isn't it a GUID?
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How to use Guids in C#?
This Code:
Something = new Guid()
is returning:
00000000-0000-0000-0000-000000000000
all the time and I can't tell why? So, why?
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How to declare a constant Guid in C#?
Is it possible to declare a constant Guid in C#?
I understand that I can declare a static readonly Guid, but is there a syntax that allows me to write const Guid?
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C# guid and SQL uniqueidentifier
I want to create a GUID and store it in the DB.
In C# a guid can be created using Guid.NewGuid(). This creates a 128 bit integer. SQL Server has a uniqueidentifier column which holds a huge ...
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How to create a GUID in Excel?
I need a function to add a GUID to cells in excel. I found this previous question on stackoverflow, but it is not working. It suggests the following function:
=CONCATENATE(DEC2HEX(RANDBETWEEN(0,...
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Check if Nullable Guid is empty in c#
Quoting from an answer from this question.
Guid is a value type, so a variable of type Guid can't be null to
start with.
What then if I see this?
public Nullable<System.Guid> SomeProperty ...
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What are the performance improvement of Sequential Guid over standard Guid? [closed]
Has someone ever measured performance of Sequential Guid vs. Standard Guid when used as Primary Keys inside a database?
I do not see the need for unique keys to be guessable or not, passing them from ...
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Why are there dashes in a .NET GUID?
Why are there dashes in a .NET GUID? Are there dashes in most implementations of a GUID, or is it just a Microsoft thing?
Signed,
741ecf77-9c92-4435-8e6b-85975bd13452
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Generate GUID in Windows with batch file
How can I generate a GUID in a batch file running using the commandline in Windows?
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What's the C++ version of Guid.NewGuid()?
I need to create a GUID in an unmanaged windows C++ project. I'm used to C#, where I'd use Guid.NewGuid(). What's the (unmanaged windows) C++ version?
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