om du använder SQL Server,
dateadd(DAY,0, datediff(day,0, created))
kommer att returnera den skapade dagen
till exempel, om försäljningen skapades den '2009-11-02 06:12:55.000',dateadd(DAY,0, datediff(day,0, created))
returnera '2009-11-02 00:00:00.000'
select sum(amount) as total, dateadd(DAY,0, datediff(day,0, created)) as created
from sales
group by dateadd(DAY,0, datediff(day,0, created))