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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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Sequential Guid Generator

Is there any way to get the functionality of the Sql Server 2005+ Sequential Guid generator without inserting records to read it back on round trip or invoking a native win dll call? I saw someone answer with a way of using rpcrt4.dll but I'm not…
Chris Marisic
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How Random is System.Guid.NewGuid()?

I know this may sounds like a pointless question, but hear me out... I basically want to know if I can trust the GUID to generate a value which will be unique 100% of the time and impossible to predict. I'm basically rolling my on login system for a…
GateKiller
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Can we use Guid as a Primary Key in Sqlite Database

Is is possible to use GUID as primary Keys in SQLITE Database?If Possible which datatype can be used?
user2134137
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What is a good unique PC identifier?

I've been looking at the code in this tutorial, and I found that it uses My.Computer.Name to save settings that shouldn't roam between computers. It's entirely possible, however, for a user to have two identically named PCs. If they wanted to have…
dlras2
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How Random is System.Guid.NewGuid()? (Take two)

Before you start marking this as a duplicate, read me out. The other question has a (most likely) incorrect accepted answer. I do not know how .NET generates its GUIDs, probably only Microsoft does, but there's a high chance it simply calls…
Vilx-
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How does C# generate GUIDs?

How are GUIDs generated in C#?
Developer404
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How are .NET 4 GUIDs generated?

I am aware of the multitude of questions here as well as Raymond's excellent (as usual) post. However, since the algorithm to create GUIDs was changed apparently, I found it hard to get my hands on any up-to-date information. The MSDN seems to try…
mafu
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Guid == null should not be allowed by the compiler

The behaviour described below is specific to .net-3.5 only I just ran across the most astonishing behavior in the C# compiler; I have the following code: Guid g1 = Guid.Empty; bool b1= (g1 == null); Well, Guid is not nullable therefore it can…
Luis Filipe
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Is there a GUID.TryParse() in .NET 3.5?

UPDATE Guid.TryParse is available in .NET 4.0 END UPDATE Obviously there is no public GUID.TryParse() in .NET CLR 2.0. So, I was looking into regular expressions [aka googling around to find one] and each time I found one there was a heated…
Jack Marchetti
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Print a GUID variable

I have a GUID variable and I want to write inside a text file its value. GUID definition is: typedef struct _GUID { // size is 16 DWORD Data1; WORD Data2; WORD Data3; BYTE Data4[8]; } GUID; But I want to write its…
Jeni
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How do I obtain/use LibUUID?

I'm trying to replace a call to ::CoCreateGUID so I can generate GUIDs in a C++ program on Linux. I understand that libuuid supports this, and I've read this question. I'm a bit new to Ubuntu/GCC/Linux, so I've started off like this: #include…
waterlooalex
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What are the chances to get a Guid.NewGuid () duplicate?

Possible Duplicate: Is a GUID unique 100% of the time? Simple proof that GUID is not unique In MSDN you can read: The chance that the value of the new Guid will be all zeros or equal to any other Guid is very low. Say that you have an method that…
Niklas
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Aggregate Function on Uniqueidentifier (GUID)

Let's say I have the following table: category | guid ---------+----------------------- A | 5BC2... A | 6A1C... B | 92A2... Basically, I want to do the following SQL: SELECT category, MIN(guid) FROM myTable GROUP BY…
Heinzi
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What is the most efficient way to encode an arbitrary GUID into readable ASCII (33-127)?

The standard string representation of GUID takes about 36 characters. Which is very nice, but also really wasteful. I am wondering, how to encode it in the shortest possible way using all the ASCII characters in the range 33-127. The naive…
mark
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Convert from Oracle's RAW(16) to .NET's GUID

I'm having difficulties manually debugging an .NET application where the Guid values differ from .NET to Oracle. Where C# reads: 17D89D326C2142D69B989F5201288DBF Oracle reads: 329DD817216CD6429B989F5201288DBF How would I be able to manually…
rebelliard
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