Powershell SMO SQL还原问题

[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SqlServer.SMO") | Out-Null
[System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SqlServer.SmoExtended") | Out-Null
[Reflection.Assembly]::LoadWithPartialName("Microsoft.SqlServer.ConnectionInfo") | Out-Null
[Reflection.Assembly]::LoadWithPartialName("Microsoft.SqlServer.SmoEnum") | Out-Null

$backupFile = 'C:\Temp\User_20191029152532.bak'

$server = New-Object ("Microsoft.SqlServer.Management.Smo.Server") "(local)"
$backupDevice = New-Object("Microsoft.SqlServer.Management.Smo.BackupDeviceItem") ($backupFile, "File")
$smoRestore = new-object("Microsoft.SqlServer.Management.Smo.Restore")

$smoRestore.NoRecovery = $false;
$smoRestore.ReplaceDatabase = $true;
$smoRestore.Action = "Database"
$smoRestorePercentCompleteNotification = 10;
$smoRestore.Devices.Add($backupDevice)

$smoRestoreDetails = $smoRestore.ReadBackupHeader($server)

"Database Name from Backup Header : " +$smoRestoreDetails.Rows[0]["DatabaseName"]

$smoRestore.Database =$smoRestoreDetails.Rows[0]["DatabaseName"]

$smoRestoreFile = New-Object("Microsoft.SqlServer.Management.Smo.RelocateFile")
$smoRestoreLog = New-Object("Microsoft.SqlServer.Management.Smo.RelocateFile")

$smoRestoreFile.LogicalFileName = $smoRestoreDetails.Rows[0]["DatabaseName"]
$smoRestoreFile.PhysicalFileName = $server.Information.MasterDBPath + "\" + $smoRestore.Database + "_Data.mdf"
$smoRestoreLog.LogicalFileName = $smoRestoreDetails.Rows[0]["DatabaseName"] + "_Log"
$smoRestoreLog.PhysicalFileName = $server.Information.MasterDBLogPath + "\" + $smoRestore.Database + "_Log.ldf"
$smoRestore.RelocateFiles.Add($smoRestoreFile)
$smoRestore.RelocateFiles.Add($smoRestoreLog)

$smoRestore.SqlRestore($server)

如果我运行这个,一切正常。不过,我想提供一个变量,用于恢复备份。所以我将代码的顶部改为:

$path = 'C:\Temp'
$db_name = 'User'
$file = Get-ChildItem $path '*.bak' | Select-Object basename | Where-Object {$_.basename -like $db_name + '*' }

$backupFile = $path + '\' + $file

使用“1”参数调用“ReadBackupReader”时发生异常:“执行Transact-SQL语句或批处理时发生异常。”

+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

+FullyQualifiedErrorId:ExecutionFailureException