SQL-forespørgsel til gruppering efter dag

hvis du bruger SQL Server,

dateadd(DAY,0, datediff(day,0, created)) returnerer den oprettede dag

f.eks. hvis udsalget blev oprettet den '2009-11-02 06:12:55.000',dateadd(DAY,0, datediff(day,0, created)) returner '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))