SQL query to group by day

Question

I want to list all sales, and group the sum by day.

Sales (saleID INT, amount INT, created DATETIME)

NOTE: I am using SQL Server 2005.

Answer 1

For oracle you can

group by trunc(created);

as this truncates the created datetime to the previous midnight.

Another option is to

group by to_char(created, 'DD.MM.YYYY');

which achieves the same result, but may be slower as it requires a type conversion.