PowerShell for Windows Admins

Aug 1 2011   6:57AM GMT

Where to select

Richard Siddaway Richard Siddaway Profile: Richard Siddaway

Using select-object (aliased to select in common usage) to reduce the number of properties passing into further processing is a common aspect of using PowerShell. However, its not the only place we can do it.

Consider this scenario.

We need to test the network client on a number of remote machines. We can use Win32_NetworkClient

PS > Get-WmiObject -Class Win32_NetworkClient

__GENUS          : 2
__CLASS          : Win32_NetworkClient
__SUPERCLASS     : CIM_LogicalElement
__DYNASTY        : CIM_ManagedSystemElement
__RELPATH        : Win32_NetworkClient.Name="Microsoft Windows Network"
__DERIVATION     : {CIM_LogicalElement, CIM_ManagedSystemElement}
__SERVER         : RSLAPTOP01
__NAMESPACE      : root\cimv2
__PATH           : \\RSLAPTOP01\root\cimv2:Win32_NetworkClient.Name="Microsoft Windows Network"
Caption          : Workstation
Description      : LanmanWorkstation
InstallDate      :
Manufacturer     : Microsoft Corporation
Name             : Microsoft Windows Network
Status           : OK


Now doing this on the local machine is fine but we might want to cut back on the properties returned across the network

PS > Get-WmiObject -Class Win32_NetworkClient -Property Name, Manufacturer, Caption, Description, Status

__GENUS          : 2
__CLASS          : Win32_NetworkClient
__DYNASTY        :
__RELPATH        : Win32_NetworkClient.Name="Microsoft Windows Network"
__DERIVATION     : {}
__SERVER         :
__NAMESPACE      :
__PATH           :
Caption          : Workstation
Description      : LanmanWorkstation
Manufacturer     : Microsoft Corporation
Name             : Microsoft Windows Network
Status           : OK

This cuts down the data a bit – obviously for a class such as Win32_ComputerSystem that has a lot more properties you would get a bigger impact

Compare this to using select-object

PS > Get-WmiObject -Class Win32_NetworkClient |
select -Property Name, Manufacturer, Caption, Description, Status

Name         : Microsoft Windows Network
Manufacturer : Microsoft Corporation
Caption      : Workstation
Description  : LanmanWorkstation
Status       : OK

OK this looks better BUT remember for a remote machine the filtering happens AFTER the object has been returned.

Locally I would use select and remotely I would think about using –property on Get-WmiObject.

As so often it all depends on what you actually need to do

 Comment on this Post

There was an error processing your information. Please try again later.
Thanks. We'll let you know when a new response is added.
Send me notifications when other members comment.

REGISTER or login:

Forgot Password?
By submitting you agree to receive email from TechTarget and its partners. If you reside outside of the United States, you consent to having your personal data transferred to and processed in the United States. Privacy

Forgot Password

No problem! Submit your e-mail address below. We'll send you an e-mail containing your password.

Your password has been sent to:

Share this item with your network: