Opium mysql backup

Create a credintals file my.cnf and add the following

[client] user = dbuser password = dbpasswd

Restrict permissions of the credentials file so that only your user has access to it:

chmod 600 ~/my.cnf

Back command

/usr/bin/mysqldump --defaults-file=~/my.cnf cycling > /media/EADC-661E/radio/.hledger/db-backup/cycling-$(date +\%Y\%m\%d).sql

You can also create another cronjob to delete any backups older than 30 days:

find /path/to/backups -type f -name "*.sql" -mtime +30 -delete

Of course, you need to adjust the command according to your backup location and file names

https://linuxize.com/post/how-to-find-files-in-linux-using-the-command-line/