Grafana: Template Variables

InfluxDB: "SHOW TAG VALUES" does not support a WHERE time clause

Issue

If you use a InfluxDB Query "SHOW TAG VALUES" it returns all possible values instead of the one present in the time period selected. There is a open GitHub "Feature Request": https://github.com/influxdata/influxdb/issues/5668

Workaround "Subquery"

SELECT "host" FROM (SELECT "<value>", "host" FROM "<InfluxDB>" WHERE $timeFilter)

host = is the tag I want to limit by time
value = is a Influx FieldKey (just needs to contain any value)