Brilliant suggestion @gazpachoking! You are correct in that one must get an individual record. @mauflege: There are probably several ways to do this, but in my sample dataset I got it to work using the Extract Scalar Value feature.
Something like this should work:
import "sql"
data=from(bucket: "TEMP_DATA")
|> range(start: -2m)
|> filter(fn: (r) => r["_measurement"] == "placeholder_1")
|> group()
|> last()
|> keep(columns: ["_time"]) // not sure this line is needed
|> limit(n:1)
|> yield(name: "table1")
tempInfo = data
|> findRecord(
fn: (key) => key._measurement == "placeholder_1",
idx: 0,
)
batchinsert=from(bucket: "Bucket2")
|> range(start: tempInfo._time, stop: now())
|> filter(fn: (r) => r["_measurement"] == "placeholder_1")
|> yield(name: "table2")
