GUID (Globally Unique ID) is it unique?

[priisholm]

Hi guys

I have a question from one of our customers concerning the GUID value..

The idea is that if the GUID that ServiceNow is using is based on the MicroSoft way, then its close to unique, but not quite.. (and UUID is better......)

Is that correct?

Somewhere I have read that there are different versions of GUID... some are based on the timestamp + MAC-address of the device and some are based on a so called "secure random number generator"...

Thanks!

Soren

[corina]

Hello Soren.

The GUID is SN is unique:

Globally unique record identifier

[priisholm]

So actually ServiceNow here (in this article) is claming that GUID IS unique.  

/Soren

[gauravchoudhury]

Hi Søren,

In ServiceNow, the primary key is something that isn't related to the data itself. It is a globally unique identifier or GUID. This GUID is stored as a 32-character string, made of hexadecimal characters (the numbers 0-9 plus the letters a-f). The number of unique GUID values is so large that the probability of two accidentally being the same is negligible. This is an example GUID: 5137153cc6611227c000bbd1bd8cd2005.

This type of identifier is sometimes known as OID or object identifier. It has no special significance; it just uniquely identifies a data row. It can also be called a surrogate key.

Whenever you create a record in ServiceNow, the platform generates a new GUID. The characters generated are random-mixture of several resources, including the date and time and details specific to the instance, meaning they're not sequential or predictable. The GUID is saved alongside the record, in a special field called sys_id. The sys_id field is heavily used in the ServiceNow platform.

If the system sees -1 as a sys_id, it'll assume it is a new record and will generate a new GUID.

It is useful to examine the structure of the URL. First, spot the sys_user table. Then, spot the GUID. With these two items, the instance knows exactly what data it needs to pull up and present to you.

Source: Mastering ServiceNow by Martin Wood

[PriyankaSadhwni]

Hello All,

Is there a way to update GUID, currently it is mistakenly set as name of CI, Now I need to either update GUID or delete CI, system is not allowing both.