try this one:
@echo off
setlocal enabledelayedexpansion
rem 假设要删除C盘test文件夹里面的两天前的.db文件
set TarDir=C:\test
echo dt=date()-2>%tmp%\MyDel.vbs
echo s=right(year(dt),4) ^& right("0" ^& month(dt),2) ^& right("0" ^& day(dt),2)>>%tmp%\MyDel.vbs
echo wscript.echo s>>%tmp%\MyDel.vbs
for /f %%a in ('cscript /nologo %tmp%\MyDel.vbs') do @set DateFlag=%%a
for %%i in (C:\test\*.db) do (
set t=%%~ti
set FileDate=!t:~6,4!!t:~0,2!!t:~3,2!
if !FileDate! lss %DateFlag% del /f "%%i"
)
del %tmp%\MyDel.vbs
endlocal