Merges one csv into another csv file

Merge-CSV.ps1

function Merge-CSV
{
    [CmdletBinding()]
    param
    (
        [parameter(Mandatory=$true)][string]$PrimaryCSVPath,
        [parameter(Mandatory=$true)][string]$SecondaryCSVPath,
        [parameter(Mandatory=$true)][string]$PrimaryCSVKey,
        [parameter(Mandatory=$true)][string]$SecondaryCSVKey
    )

    begin
    {
    }
    process
    {
        $primaryCSVRows   = Import-Csv -Path $PrimaryCSVPath
        $secondaryCSVRows = Import-Csv -Path $SecondaryCSVPath

        foreach( $primaryCSVRow in $primaryCSVRows )
        {
            $secondaryCSVRow = $secondaryCSVRows | ? { $_.$SecondaryCSVKey -eq  $primaryCSVRow.$PrimaryCSVKey }

            $object = New-Object PSObject

            foreach( $property in $primaryCSVRow.PSObject.properties )
            {
                $object | Add-Member -MemberType NoteProperty -Name $property.Name -Value $primaryCSVRow.$($property.Name)
            }

            foreach( $property in $secondaryCSVRow.psobject.properties )
            {
                if( -not ($object.psobject.properties | ? Name -eq $property.Name) )
                {
                    $object | Add-Member -MemberType NoteProperty -Name $property.Name -Value $secondaryCSVRow.$($property.Name)
                }
            }

            $object
        }
    }
    end
    {
    }
}

<#

EXAMPLE PRIMARY CSV

    Login COL1 COL2 COL3
    ----- ---- ---- ----
    joe   AA   BB   CC  
    brian XX   DD   YY  



EXAMPLE SECONDARY CSV

    UserName COL3 COL4 COL5
    -------- ---- ---- ----
    joe      FF   AA   RR  
    john     II   HH   UU  


EXAMPLE OUTPUT

    Login COL1 COL2 COL3 UserName COL4 COL5
    ----- ---- ---- ---- -------- ---- ----
    joe   AA   BB   CC   joe      AA   RR  
    brian XX   DD   YY      

#>

Merge-CSV -PrimaryCSVPath "C:\_temp\PRIMARY.csv" -SecondaryCSVPath "C:\_temp\SECONDARY.csv" -PrimaryCSVKey "Login" -SecondaryCSVKey "UserName" | FT