> 対象DIR > sampleDB_2021-11-20_17-00-00.bak > sampleDB_2021-11-21_17-00-00.bak > sampleDB_2021-11-22_17-00-00.bak > sampleDB_2021-11-23_17-00-00.bak # 2件残して後は削除 Get-ChildItem | Sort-Object -Property Name -Descending | Select-Object -Skip 2 | ForEach-Object { Remove-Item $_.FullName }