How to batch backup multiple MySQL databases and save them in the same folder each time?

The mysql data generated by batch processing is backed up once a day. How to create a folder named after that day in batch processing and save the generated sql file in the folder

<code>@echo off
set "Ymd=%date:~,4%%date:~5,2%%date:~8,2%"
D:\wamp\bin\mysql\mysql5.5.24\bin\mysqldump --opt -u root --password=123456 anna > E:\crontab\mysql\sql\bbs_anna%Ymd%.sql

D:\wamp\bin\mysql\mysql5.5.24\bin\mysqldump --opt -u root --password=123456 typecho > E:\crontab\mysql\sql\bbs_typecho%Ymd%.sql
@echo on</code>