how to use entity framework to group by date not date with time

Question

my code:

//get data
var myData = from log in db.OperationLogs
              group log by log.CreateTime.Date  into g
              orderby g.Key
                     


        

Answer 1

Use EntityFunctions.TruncateTime Method (Nullable<DateTime>). It will be transalated into TRUNCATETIME() TSQL function in generated SQL query, which does what you need:

Returns the expression, with the time values truncated.

So your code should be as follows:

//get data
var myData = from log in db.OperationLogs
             group log by EntityFunctions.TruncateTime(log.CreateTime) into g
             orderby g.Key
             select new { CreateTime = g.Key, Count = g.Count() };

Answer 2

     var result = from s in entitiesModel.TvysFuelTankDatas
                           orderby s.Datetime ascending
                           group s by new { y = s.Datetime.Year, m = s.Datetime.Month + "/", d = s.Datetime.Day + "/" } into g
                           select new WellDrillData { Date = Convert.ToDateTime(g.Key.d.ToString() + g.Key.m.ToString() + g.Key.y.ToString()), Depth = (double)g.Sum(x => x.Difference) };

              List<WellDrillData> dailyFuelConsumptions = result.ToList();