How to average/sum data in a day in SQL Server 2005

Question

I\'m trying to average data in SQL Server 2005 in a day. Here is what my database look like this if I use simple query as

SELECT timestamp, FEED
FROM ROASTE         


        

Answer 1

try this:

SELECT timestamp, sum(FEED)
FROM ROASTER_FEED
WHERE timestamp=....
GROUP BY timestamp

it could be slow if you are handling alot of data, in this case you should considering an additional table which holds the pre-calculated values for each day.