PromQL is one of the core features of Prometheus, allowing for powerful analysis and processing of time series.
Although QL is in the name, it is not related to SQL. Relational algebra doesn't work too well for typical calculations on multi-dimensional time series. Syntax wise, PromQL is closest to expressions in the C family of languages.
This course looks at each of the components of PromQL in turn, building up to real life use cases. This course is targeted towards Prometheus 2.0, though most of the material will also apply to older versions.