function Format-ConfigurationDataMergeKey {
    [CmdletBinding()]
    Param(
        [AllowNull()]
        $Item,
        [Parameter(Mandatory=$true)]
        [String[]]
        $KeyNames
    )

    $Pairs = foreach($KeyName in $KeyNames){
        "$KeyName=$(Get-ConfigurationDataItemValue -Item $Item -KeyName $KeyName)"
    }

    return ($Pairs -join ", ")
}