Compare CSV files using Powershell

I have two very large CSV files both with the following headings 'Name', FullName','Length'.
What I am looking for is a way to compare these CSV files in Powershell.

I need to know...

1) What files are unique to each set (Based purely on Name).
2) What files exist in both but whos lengths are different (Based on Name and Length).

Basically a report on what changes are represented between the two CSV files... If the results could be output to seperate files representing each type of difference that would be ideal?

This is to solve a problem where a new version of software has grown rapidly in size but the cause of the growth is unknown.
Who is Participating?
footechConnect With a Mentor Commented:
Using the fullname would avoid errors.  All you would have to do to modify the script is change each instance of "Name" to "FullName".
Let me know how the below works for you.  The output files only include the file names.  If you need it to be something else, let me know if you need help making the adjustment to the code.  Hope that all files names are unique in each .CSV, otherwise this won't work.
$file1 = Import-CSV file1.csv
$file2 = Import-CSV file2.csv
Compare-Object $file1 $file2 -Property Name | Select -ExpandProperty Name | Out-File UniqueFiles.txt
($file1 + $file2) | Group -Property Name |
 ? { $_.count -eq 2 } |
 % { Compare-Object ($[0] ($[1] -property Name,Length -passthru } |
 Select -ExpandProperty Name -ExcludeProperty SideIndicator -Unique |
 Out-File ChangedSize.txt

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Blowfelt82Author Commented:
Its basically a comparison of a c:\ drive exported from a wim file, so there may well be duplicated names... Perhaps using the fullpath field would give greater acuracy?
Blowfelt82Author Commented:
Thanks again for your help
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