How to: Histogram support
![Histogram](https://github.com/Altinity/clickhouse-grafana/raw/master/src/img/histogram.png)

To show Histogram you need query in format as "Time Series"

According to https://grafana.com/docs/grafana/latest/panels-visualizations/visualizations/histogram, Histograms support time series and any table results with one or more numerical fields.