Generating Pseudo GUIDs for Your Project Server Entities

As you might have known, since the version 2013, Project Server utilizes pseudo-GUIDs to improve Project Server performance. These ones has the format of a “classical” GUID, but actually generated sequentially. As Microsoft states in this TechNet article:

"We handle GUIDs a little better in Project Server 2013 – and in many places they are sequential GUIDs which cause less index fragmentation"

This topic is quite good described in the Project Conference 2014 presentation Project Worst Practice – Learning from other peoples mistakes by Brian Smith. See the video recording between 6:08-13:54, or the slides 10-14.

One of the main components of the pseudo-GUID generation is the NewSequentialUid method of the Microsoft.Office.Project.Server.Library.PSUtility class:

public static Guid NewSequentialUid() 
{ 
  Guid guid; 
  if (NativeMethods.UuidCreateSequential(out guid) != 0) 
    return Guid.NewGuid(); 
  byte[] b = guid.ToByteArray(); 
  Array.Reverse((Array) b, 0, 4); 
  Array.Reverse((Array) b, 4, 2); 
  Array.Reverse((Array) b, 6, 2); 
  return new Guid(b); 
}

So if you want to use the same kind of pseudo-GUIDs for your own custom entities you create from code, you can get the IDs by invoking the method (for example, via PowerShell). The code sample below illustrates, how to get a single ID, or a batch of  IDs (in this case, 5 of them):

# load the necessary assembly
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.Office.Project.Shared")
# generate a single sequential ID
[Microsoft.Office.Project.Server.Library.PSUtility]::NewSequentialUid()
# or generate a range of sequential IDs, in this case, five of them
(1..5) | % { [Microsoft.Office.Project.Server.Library.PSUtility]::NewSequentialUid().Guid }