PriorityClass

PowerShell Help
1

The ff statement works just fine

Get-Process | Group-Object -Property PriorityClass

But when I add the second line (to obtain only High and AboveNormal):

 Get-Process | Group-Object -Property PriorityClass |
Where-object {$_.Name -eq 'AboveNormal' -or $_.Name -eq 'High'}

I get the expected (and correct) output, but additionally, the following error message twice:

Group-Object : Exception getting “PriorityClass”: “Access is denied”
At line:2 char:15

  • Get-Process | Group-Object -Property PriorityClass |
  • CategoryInfo : InvalidResult: (System.Diagnostics.Process (Idle):PSObject) [Group-Object], Get
    ValueInvocationException
  • FullyQualifiedErrorId : ExpressionEvaluation,Microsoft.PowerShell.Commands.GroupObjectCommand

My understanding of Group-objector its syntax when piping to Where-object must be missing something.Would be grateful for any advice or tips.

 

2

I cannot explain why this happens but you could try to specify what properties you’re after with your Get-Process. At least in my environment it works this way. :wink: 

Get-Process |

Select-Object -Property ProcessName,MainWindowTitle,PriorityClass |

Group-Object -Property PriorityClass |

Where-Object {$.Name -eq ‘AboveNormal’ -or $.Name -eq ‘High’}

3

Many thanks Mr Olaf Soyk,

I will most certainly try your suggestion. This has been mind-boggling … At first I wished I had a second laptop nearby to “reproduce” the error – if the error message is to be believed and truly the reason. (no access rights). But since you experienced the same (I assume, from your response), I now assume this is a reproducible error.

The puzzling thing is it still gave me the correct outputs – i.e., identical to the one-liner (which had additional for Normal and Low priorities).

Thanks again,

4

It’s best to select before a group.
So, why not just do this…

 Get-Process | Select PriorityClass | Group-Object -Property PriorityClass |
Where-object {$_.Name -eq 'AboveNormal' -or $_.Name -eq 'High'}

Count Name        Group                                                                                     
----- ----        -----                                                                                     
    3 High        {@{PriorityClass=High}, @{PriorityClass=High}, @{PriorityClass=High}}                     
    3 AboveNormal {@{PriorityClass=AboveNormal}, @{PriorityClass=AboveNormal}, @{PriorityClass=AboveNormal}}

Or this…

Get-Process | Select PriorityClass | Group-Object -Property PriorityClass |
Where-object {$_.Name -eq 'AboveNormal' -or $_.Name -eq 'High'} | 
Select Count,Name

Count Name       
----- ----       
    3 High       
    3 AboveNormal

Or even this

 (Get-Process | Select-Object PriorityClass) -match 'AboveNormal|High' | Group-Object -Property PriorityClass

Count Name        Group                                                                                     
----- ----        -----                                                                                     
    3 High        {@{PriorityClass=High}, @{PriorityClass=High}, @{PriorityClass=High}}                     
    3 AboveNormal {@{PriorityClass=AboveNormal}, @{PriorityClass=AboveNormal}, @{PriorityClass=AboveNormal}}

… as you will note, no error are generated.

5

Many thanks, Mr PostaNote … you have given me excellent examples and they have given me new insights into Powershell.

Much appreciated.