@echo off

for /F "usebackq tokens=1,2 delims==" %%i in (`wmic os get LocalDateTime /VALUE 2^>NUL`) do if '.%%i.'=='.LocalDateTime.' set ldt=%%j

set ldtstr=%ldt:~0,4%_%ldt:~4,2%_%ldt:~6,2%_%ldt:~8,2%_%ldt:~10,2%_%ldt:~12,2%_%ldt:~15,3%

mysqldump --host=192.168.1.102 --user=root --password=root -B -E -R ems > ems_jg%ldtstr%.sql