I wrote this code. But I want to ignore time, I want to compare only day.
from s in sayac_okumalari
where s.okuma_tarihi == startDate && s.sayac_id == sayac_id
group s by new { date = new DateTime(((DateTime)s.okuma_tarihi).Year, ((DateTime)s.okuma_tarihi).Month, ((DateTime)s.okuma_tarihi).Day, ((DateTime)s.okuma_tarihi).Hour, 1, 1) } into g
select new
{
okuma_tarihi = g.Key.date,
T1 = g.Sum(x => x.toplam_kullanim_T1),
T2 = g.Sum(x => x.toplam_kullanim_T2),
T3 = g.Sum(x => x.toplam_kullanim_T3)
};
for example:
25.02.1987 == 25.02.1987
use s.okuma_tarihi.Value.Date == startDate.Date
. This should allow you to compare only the Date component.
Update From the discussion in comments looks like the user is using NullableType. Hence updated the solution for NullableType.