Alerting on numeric data

This feature is supported with backend data sources that query tabular data:

• SQL data sources such as MySQL, Postgres, MSSQL, and Oracle.

• The “Format AS” option is set to “Table” in the data source query.

If there are string columns then those columns become labels. The name of column becomes the label name, and the value for each row becomes the value of the corresponding label. If multiple rows are returned, then each row should be uniquely identified their labels.

Example

You can query the data filtering on time, but without returning the time series to Grafana. For example, an alert that would trigger per Host, Disk when there is less than 5% free space:

When this query is used as the condition in an alert rule, then the non-zero will be alerting. As a result, three alert instances are produced: