Why is it better to use Get-ADUser -Filter {GivenName -eq “John”} in comparison to Get-AdUser -Filter * Where-Object

Using the -Filter parameter with the Get-ADUser cmdlet is generally more efficient than using the Where-Object cmdlet to filter the results of the Get-ADUser cmdlet.

When you use the -Filter parameter, the filtering is done by the Active Directory service, which is optimized for this task. On the other hand, when you use the Where-Object cmdlet, the filtering is done in the client side by the PowerShell process, which can be slower.

Additionally, using the -Filter parameter can reduce the amount of data that needs to be transferred over the network, as only the matching AD users are returned to the client. When you use the Where-Object cmdlet, all AD users are returned to the client and then filtered, which can use more network bandwidth.

Therefore, it is generally recommended to use the -Filter parameter whenever possible to optimize the performance and efficiency of your PowerShell scripts that query Active Directory.

In the example you provided, Get-ADUser -Filter {GivenName -eq "John"} will return only the AD users with a given name of “John”, while Get-AdUser -Filter * | Where-Object will return all AD users and then filter them based on the condition specified in the Where-Object cmdlet.