Windows搜索查询的总结果

Question

我正在尝试使用PowerShell和Windows搜索来获取我的磁盘使用情况的一些统计信息。这就是我现在提出的问题：

$sql        = "SELECT System.FileExtension, System.Size FROM SYSTEMINDEX WHERE DIRECTORY = 'C:\Users\...\Documents' AND System.FileExtension = '.docx'"
$provider   = "provider=search.collatordso;extended properties=’application=windows’;" 
$connector  = New-Object System.Data.OleDb.OleDbDataAdapter -Argument $sql, $provider 
$dataset    = New-Object System.Data.DataSet

if ($connector.fill($dataset)) {
    $res = $dataset.Tables[0]

    $res | Group-Object System.FileExtension |
        Select-Object System.FileExtension,
            @{Name='Total';Expression={($_.Group | Measure-Object SYSTEM.Size -Sum).Sum}} |
        Format-Table
}

这很有效，但看起来很难看。我也发现并尝试过这个：

$sql       = "SELECT System.Size FROM SYSTEMINDEX WHERE DIRECTORY = 'C:\Users\...\Documents' AND System.FileExtension = '.docx'"
$provider  = "provider=search.collatordso;extended properties=’application=windows’;" 
$connector = New-Object System.Data.OleDb.OleDbDataAdapter -Argument $sql, $provider 
$dataset   = New-Object System.Data.DataSet

if ($connector.fill($dataset)) {
    $dataset.Tables[0].Compute("Sum(SYSTEM.Size)")
}

看起来好多了，但却抛出错误：

  

无法找到＆＃34; Compute＆＃34;参数计数：＆＃34; 1＆＃34;