How to write a shell script to check the mysql database backup status.
This would indeed be nice to be able to do it in an automatic way. Unfortunately, to be 100% sure your backups are fine, you need human intervention. After taking the backup, you must be able to check if you can import it safely. Of course, you can not always do it. You can check your backups for example every 2-4 days.

On the other hand, you can always check if the size of the new backup is significantly smaller than the previous one (considering that the database always increases in size). This could be an indication that your backup might not have been taken correctly or is corrupted.