SQL Server GROUP BY datetime ignore hour minute and a select with a date and sum value

Question

I have a table with two fields - datetime and int. I want to do a group by on the datetime only on the date ignoring the hour and minute.

Answer 1

Personally i prefer the format function, allows you to simply change the date part very easily.

     declare @format varchar(100) = 'yyyy/MM/dd'
     select 
        format(the_date,@format), 
        sum(myfield) 
     from mytable 
     group by format(the_date,@format) 
     order by format(the_date,@format) desc;