Export local phpmyadmin data via CMD

First go the mysql folder where your localhost install. in my case I'm using xampp.
In reqular xampp password will be blank as default unless you set something. If it is blank then you can just leave as blank like
--password=
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1. cd C:\xampp\mysql\bin
2. mysqldump --user=root --password=password mydbname > mydbname-backup.sql
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Backup file will be avaliable in C:\xampp\mysql\bin folder.

For more info visit.

https://learntech.imsu.ox.ac.uk/blog/mysqldump-all-databases-from-xampp-on-windows/
https://stackoverflow.com/a/13484728