Subquery with group by time in outer query

1

SELECT mean(DCTBH) from (SELECT derivative(“CTBH”, 1d) as DCTBH FROM “sensors” WHERE $timeFilter) GROUP BY time(1h)

returns “aggregate function required inside the call to derivative”

Is this the expected behavior?

2

Hello @nathanp,

Yes. Your query needs to look like this:

SELECT DERIVATIVE(AGGREGATION_FUNCTION(<field_key>),[<unit>]) FROM <measurement_name> WHERE <stuff> GROUP BY time(<aggregation_interval>)

Please take a look at the documentation and this issue for more help.

Best,

Anais

3

That doesn’t do the same thing as the intent of my query. With that syntax the aggregate function is applied first, then the derivative. I want to apply the derivative first, then the aggregate function. Is that possible?