我如何獲得這個SQL到LINQ？多組

Question

對於一個db人，LINQ可能會令人沮喪。我需要將以下SQL轉換爲Linq。

SELECT COUNT(o.objectiveid), COUNT(distinct r.ReviewId), l.Abbreviation 
FROM Objective o 
JOIN Review r 
    on r.ReviewId = o.ReviewId 
    and r.ReviewPeriodId = 3 
    and r.IsDeleted = 0 
JOIN Position p 
    on p.PositionId = r.EmployeePositionId 
    and p.DivisionId = 2 
JOIN Location l 
    on l.LocationId = p.LocationId  
GROUP BY l.Abbreviation  

group by nested example可能是我必須去的方式，但不確定。 做一組由我用下面的代碼：

var query = from rev in db.Reviews 
           .Where(r => r.IsDeleted == false && r.ReviewPeriodId == reviewPeriodId) 
       from obj in db.Objectives 
           .Where(o => o.ReviewId == rev.ReviewId && o.IsDeleted == false) 
       from pos in db.Positions 
           .Where(p => rev.EmployeePositionId == p.PositionId && p.IsDeleted == false && p.DivisionId == divisionId) 
       from loc in db.Locations 
           .Where(l => pos.LocationId == l.LocationId) 
       group loc by loc.Abbreviation into locgroup 

       select new ReportResults 
       { 
       KeyId = 0, 
       Description = locgroup.Key, 
       Count = locgroup.Count() 
       }; 

    return query.ToList(); 

什麼是正確的方法是什麼？

感謝

Answer 1

我知道你在問一個具體的，但也有一些工具，在那裏你也許可以利用學習SQL到LINQ。檢查出來，看看他們是否幫助！通過第一個工具運行你的SQL查詢，看看它出現了什麼。

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