compare two csv using powershell and return matching and non-matching values - powershell

Question

I have two csv files, i want to check the users in username.csv matches with userdata.csv copy
to output.csv. If it does not match return the name alone in the output.csv
For Ex: User Data contains 3 columns
UserName,column1,column2
Hari,abc,123
Raj,bca,789
Max,ghi,123
Arul,987,thr
Prasad,bxa,324
username.csv contains usernames
Hari
Rajesh
Output.csv should contain
Hari,abc,123
Rajesh,NA,NA
How to achieve this. Thanks
Sorry for that.
$Path = "C:\PowerShell"
$UserList = Import-Csv -Path "$($path)\UserName.csv"
$UserData = Import-Csv -Path "$($path)\UserData.csv"
foreach ($User in $UserList)
{
ForEach ($Data in $UserData)
{
If($User.Username -eq $Data.UserName)
{
# Process the data
$Data
}
}
}
This returns only matching values. I also need to add the non-matching values in output
file. Thanks.

Answer 1

something like this will work:
$Path = "C:\PowerShell"
$UserList = Import-Csv -Path "$($path)\UserName.csv"
$UserData = Import-Csv -Path "$($path)\UserData.csv"
$UserOutput = #()
ForEach ($name in $UserList)
{
$userMatch = $UserData | where {$_.UserName -eq $name.usernames}
If($userMatch)
{
# Process the data
$UserOutput += New-Object PsObject -Property #{UserName =$name.usernames;column1 =$userMatch.column1;column2 =$userMatch.column2}
}
else
{
$UserOutput += New-Object PsObject -Property #{UserName =$name.usernames;column1 ="NA";column2 ="NA"}
}
}
$UserOutput | ft
It loops through each name in the user list. Line 9 does a search of the userdata CSV for a matching user name if it finds it it adds the user data for that user to the output if no match is found it adds the user name to the output with NA in both columns.
had to change your userList csv:
usernames
Hari
Rajesh
expected output:
UserName column1 column2
-------- ------- -------
Hari abc 123
Rajesh NA NA

Answer 2

I had a similar situation, where I needed a "changed record collection" holding the entire record when the current record was either new or had any changes when compared to the previous record. This was my code:
# get current and previous CSV
$current = Import-Csv -Path $current_file
$previous = Import-Csv -Path $previous_file
# collection with new or changed records
$deltaCollection = New-Object Collections.Generic.List[System.Object]
:forEachCurrent foreach ($row in $current) {
$previousRecord = $previous.Where( { $_.Id -eq $row.Id } )
$hasPreviousRecord = ($null -ne $previousRecord -and $previousRecord.Count -eq 1)
if ($hasPreviousRecord -eq $false) {
$deltaCollection.Add($current)
continue forEachCurrent
}
# check if value of any property is changed when compared to the previous
:forEachCurrentProperty foreach ($property in $current.PSObject.Properties) {
$columnName = $property.Name
$currentValue = if ($null -eq $property.Value) { "" } else { $property.Value }
$previousValue = if ($hasPreviousRecord) { $previousRecord[0]."$columnName" } else { "" }
if ($currentValue -ne $previousValue -or $hasPreviousRecord -eq $false) {
$deltaCollection.Add($currentCenter)
continue forEachCurrentProperty
}
}
}