Are Calculated columns dynamic?

Question

I have got two columns and one is calculating by using the other. But i want to catch TODAY's date and make them calculate with this data. But whenever i change the date , the columns is not changing. How can i do this?

Answer 1

calculated columns are updated only when you update/edit item.
If you want to have column that calculates exp. Today-2 (two days ago) and to have it everyday fresh, one way to do it is to create task scheduler. Task scheduler will call at some time (you will decide when will it be) powershell script. PS script will go through list and refresh all items but will not update your items, so version of items will not be changed nor will be changed items columns modified by and modified.

I had similar task, here is explanation of solution I implemented, if you want to do it this way.

$web = Get-SPWeb http://Server/ListLocation
$list = $web.Lists["ListA"]

foreach ($item in $list.Items)
{
  $item.UpdateOverwriteVersion();
}