To create a backup of your MySQL database, you can use our PHPMyAdmin page for that. To access it, please follow these steps:
1. Login to Plesk? 
2. Go to Database menu
3. On your database name row, you can click "Webadmin" icon/menu
4. You will be redirected to PHPMyAdmin page
5. on the PHPMyAdmin Page, click your database
6. And then click Export
7. Choose "Quick - display only the minimal options"
8. Click Go. Your database file is downloaded to your local computer.