Question

I have been tasked with creating a SQL query (limited knowledge) that will show my max temperature and minimum temperature during the day. The information in the db has timestamps every 20 seconds with the point values. I’d like to just see the max temperature for each day.

I know how to do the MAX and Min:

SELECT 
    MIN (pv) As MinimumTemperature
FROM 
    plexxium201.dbo.pv_history

SELECT  
    MAX (pv)
FROM 
    plexxium201.dbo.pv_history

I’m just having problems with the date, since there are entries every 20 seconds for a day. Any help would be appreciated.

Answer 1

SELECT MIN (pv) As MinimumTemperature, MAX (pv) as MaxTemp, YEAR(datefield) as year, MONTH(datefield) as month, DAY(datefield) as day
FROM plexxium201.dbo.pv_history
GROUP BY YEAR(datefield), MONTH(datefield), DAY(datefield)

There is also a way to do this with windowing — but I think this will serve your needs.