DatadogDatadog and Prometheus both handle metrics and alerting, but Datadog is a managed SaaS with a broad observability suite, while Prometheus is an open-source monitoring system built around its own time-series database for cloud-native metrics.
Prometheus and InfluxDB are both time-series databases for monitoring, but differ in architecture and query approach. Prometheus uses a pull model with PromQL, while InfluxDB uses push with InfluxQL or SQL.