I want to disable list throttling on a particular list using PowerShell, will this cause any performance issues when the list contains more than 20000 items?
It is not recommended scenario. Microsoft is saying that it might cause performance problems. In my experience it depends on hardware resources, number of concurrent users accessing the list. I would really suggest, if possible, to test it first. 20000 is quite a lot (when you consider 5000 throttling default limit).
It is recommended to either split items into folders (in the same list) or create views filtered by indexed column. Usually there is not many scenarios where users need to be returned more than 5000 items, but I understand that there might be such requirement.
Use this to disable throttling for a single list:
$web = Get-SPWeb http://url/sites/web $list = $web.Lists["List Name"] $list.EnableThrottling = $false $list.Update()
Well you may find similar code for disabling throttling of a SharePoint list but one thing I don’t like is specifying SharePoint objects without taking care of case sensitivity, as Powershell will not recognize objects.
$WebURL = "http://local/Sites/Solutions" $ListName = "YouDesiredList" $web = Get-SPWeb $WebURL $List = $Web.Lists[$ListName] $list.EnableThrottling = $false $List.Update()