通過現場使用LINQ to組數據集，並計算基於where子句

Question

我有這個數據庫設計一個又一個的總和：

StartDate    Number Branch 
2/23/2014 3:00:00 AM 2  1 
2/23/2014 3:00:00 AM 3  1 

我如何使用LINQ組由startdate，總結了number並且其中branch = 1

結果必須能夠循環以獲得總數。

Answer 1

這是相當直截了當：

var result = db.myTable.Where(x => x.Branch == 1) 
         .GroupBy(x => x.StartDate) 
         .Select(g => new 
         { 
          StartDate = g.Key, 
          Sum = g.Sum(x => x.Number) 
         }); 

或者在查詢語法：

var result = 
    from x in db.myTable 
    where x.Branch == 1 
    group x by x.StartDate into g 
    select new 
    { 
     StartDate = g.Key 
     Sum = g.Sum(x => x.Number) 
    };