增量GUID和唯一标识符 [英] Incremental GUID and unique identifier

问题描述

我想使用C#和SQL Server按顺序生成Guid

例如

00000000-0000-0000-0000-000000000000
00000000-0000-0000-0000-000000000001
00000000-0000-0000-0000-000000000002
...................................
00000000-0000-0000-0000-00000000000F
00000000-0000-0000-0000-000000000010
.................
.............
4FF2EAFF-32BF-445D-8A61-2A9303828C2D

我需要能够在SQL Server中做到这一点(例如为int设置身份规范)
我需要像Guid.NextGuid()这样在C#中执行此操作，并且它会递增.

Thanx

I would like to generate Guids in Order using C# and SQL Server

Eg

00000000-0000-0000-0000-000000000000
00000000-0000-0000-0000-000000000001
00000000-0000-0000-0000-000000000002
...................................
00000000-0000-0000-0000-00000000000F
00000000-0000-0000-0000-000000000010
.................
.............
4FF2EAFF-32BF-445D-8A61-2A9303828C2D

I need to be able to do this in SQL server (like setting identity spec for int)
and I need to do this in C# like Guid.NextGuid() and it increments.

Thanx

推荐答案

我同意Kieth Barrow提出的解决方案".这样做确实是在滥用GUID字段.

话虽这么说，您有几种选择比尝试做的要容易.您需要多少条记录才能唯一标识?您可以使用BigInt，它允许的数字介于-9,223,372,036,854,775,808和9,223,372,036,854,775,807之间.

该表定义将允许18,446,744,073,709,551,615个唯一键.

I agree with the "solution" proposed by Kieth Barrow. It''s you''re really abusing the GUID field by doing this.

That being said you have a few options easier than what you''re trying to do. How many records are do you need to uniquely identify? Chances are you can use BigInt which allows numbers between -9,223,372,036,854,775,808 and 9,223,372,036,854,775,807.

This table definition would allow for 18,446,744,073,709,551,615 unique keys.

Create table Test (
    Key    bigint identity(-9223372036854775808, 1)
)

您可以使用十进制，这将允许-10e + 38到10e + 38

You could use decimal which would allows -10e+38 to 10e+38

create table Test (
    Key    test1 decimal(38,0) identity(-10000000000000000000000000000000000000,1)
)

这将为您提供2e + 38的值，这仍然比一个Guid所能达到的〜3.4e + 38值略短，但是如果您需要那么多，我会感到震惊.


2e + 38 = 2十亿= 20,000,000,000,000,000,000,000,000,000,000,000,000,000,000

That would give you 2e+38 values, which is still a little short of the ~3.4e+38 values you could have with a guid, but I''d be shocked if you need that many.


2e+38 = 2 Undecillion = 20,000,000,000,000,000,000,000,000,000,000,000,000

这超出了GUID的观点.他们应该是随机的，以至于它们非常独特.对于 G 全局 U nique ID 读取"通用唯一 ID(几乎可以保证:))"
通过像这样顺序生成值，就打破了它们的意义:如果从头开始运行代码，您将获得两次相同的"GUID".

您应该选择使用GUID或自动递增索引，但不能同时使用两者.如果您要实现的目标背后有原因，可以将其添加到您的问题中，并针对您已对其进行更新的回复发表评论.我再看一遍.

That defeats the point of a GUID. They are supposed to be random to the point that they are pretty much unique. for Globally Unique ID read "Universally Unique Id (almost guaranteed :))"
By generating values sequentially like this you are breaking the point of them: if you run your code from scratch you will get the same "GUID" twice.

You should settle on either a GUID or a Auto incrementing index, you can''t have both. If there is a reason behind what you are trying to achieve, can you add it to your question, and comment on this reply that you have updated it. I''ll take another look.

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