HeidiSQL - HeidiSQL is a powerful and easy client for MySQL, MariaDB, Microsoft SQL Server and PostgreSQL. Open source and entirely free to use.
Zabbix - Track, record, alert and visualize performance and availability of IT resources
Adminer - Adminer (formerly phpMinAdmin) is a full-featured database management tool written in PHP.
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
phpMyAdmin - phpMyAdmin is a tool written in PHP intended to handle the administration of MySQL over the Web.
Prometheus - An open-source systems monitoring and alerting toolkit.