import "array"
array.from(rows: [
{_time: 2021-01-01T00:00:00Z, _value: "foo"},
{_time: 2020-01-02T00:00:00Z, _value: "bar"}
])

import "array"
array.from(rows: [
{a: display(v: "${host}")}
])
import "array"
import "strings"
array.from(rows: [
{a: 1, b: display(v:
strings.split(v: "dallas-testnet-relayer-1_67euUv", t:"_")[0])}
])
|> filter(fn: (r) => r["host"] == strings.split(v: "${host}", t:"_")[0] or r.host =~ /relayer/)
|> filter(fn: (r) => contains(value: r.host, set: [${host:json}]))
|> filter(fn: (r) => r.host =~ /${host:regex}/)