This repo contains various different zabbix templates.
This template runs an SSH check for the number of DB partitions for your environment. You may want to add more checks for additional days in the future, to do so you just need to copy the item and update the XXXXXXXX value for the check:
ls /var/lib/mysql/zabbixdb | grep -c $(date -d "$(date +%F)"+XXXXXXXXdays "+%Y%m%d")
Note You will likely need to change the ls /var/lib/mysql/zabbixdb location to be where your Zabbix database lives on the host you are checking.