How do I use LastWriteTime when comparing files in different folder - powershell

Question

This script compare FILE objects by Name, Length, and LastWriteTime.
cls
$Source= "C:\Source"
$Destination = "C:\Destination"
Compare-Object (ls $Source) (ls $Destination) -Property Name, Length, LastWriteTime | Sort-Object {$_.LastWriteTime} -Descending
Output:
Name Length LastWriteTime SideIndicator
---- ------ ------------- -------------
11.0.3127.0.txt 6 8/31/2013 10:01:19 PM <=
11031270.txt 0 8/31/2013 9:43:41 PM <=
11.0.3128.0.txt 13 8/31/20131:20:15PM =>
11.0.3129.0.txt 0 8/28/2013 11:34:38 AM <=
I need to create a script that retrive the current DB version and checks if single or multiple patches are available.
The way it works is the following:
Run a SQL Query against a DB
Store the SQL Info onto a fileName (eg.11.0.3128.0.txt) on C:\Destination
Compare the information in the .txt file against the files/patches present in the Source folder
List item
If Source folder contains older files/patches -- do nothing
If Source folder contain newer files, then copy those files to C:\NewPatchFolder
Then run a script to apply all the new patches
I already took care of #1, #2. I was planning to modify/add on to above script to simplify the steps in #3, #4 and #5.
Is it possible to modify above script to achive my goals as follow:
compare LastWriteTime from the files in C:\Source folder with the file in C:\Destination
copies the files in C:\Source folder to C:\NewPatchFolder if LastWriteTime is equal or greater then the LastWriteTime of the file on the C:\Destination folder

Answer 1

I wouldn't use Compare-Object for this. Try the following:
Get-ChildItem $Source | % {
$f = Join-Path $Destination $_.Name
if (Test-Path -LiteralPath $f) {
if ($_.LastWriteTime -ge (Get-Item $f).LastWriteTime) {
Move-Item $_.FullName 'C:\NewPatchFolder'
}
}
}