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c#linqleft-joinright-join

Outer right join on Linq c#


How can I perform a right join ? I'm trying to use the DefaultIfEmpty() function, but without effect.

There is my code :

 var AbsByDepartmentADM = (from abs in _dbContext.Absences
                              join e in _dbContext.DepartementProjects on abs.DepartementProjectID equals e.Id

                              into g 

                              from c in g.DefaultIfEmpty()
                                  where abs.Profil == "SHT"

                                  group abs by new { abs.DepartementProject.Label } into z
                              select new 
                              {
                                  Matricule = z.Key.Label,
                                  NumberOfAbsence = z.Count(),
                                  WorkedHours = z.Sum(a => a.WorkedHours),
                                  AbsencesHours = (8* z.Count() - z.Sum(a => a.WorkedHours))

                              } into H

                              orderby H.NumberOfAbsence descending
                              select H);

The sql query generated :

{SELECT 
[Project1].[C3] AS [C1], 
[Project1].[Label] AS [Label], 
[Project1].[C1] AS [C2], 
[Project1].[C2] AS [C3], 
[Project1].[C4] AS [C4]
FROM ( SELECT 
   [GroupBy1].[A1] AS [C1], 
   [GroupBy1].[A2] AS [C2], 
1 AS [C3], 
 CAST( 8 * [GroupBy1].[A3] AS float) - [GroupBy1].[A4] AS [C4], 
[GroupBy1].[K1] AS [Label]
FROM ( SELECT 
    [Extent2].[Label] AS [K1], 
    COUNT(1) AS [A1], 
    SUM([Extent1].[WorkedHours]) AS [A2], 
    COUNT(1) AS [A3], 
    SUM([Extent1].[WorkedHours]) AS [A4]
    FROM  [dbo].[Absences] AS [Extent1]
    INNER JOIN [dbo].[DepartementProjects] AS [Extent2] ON [Extent1].[DepartementProjectID] = [Extent2].[Id]
    WHERE N'SHT' = [Extent1].[Profil]
    GROUP BY [Extent2].[Label]
)  AS [GroupBy1]
)  AS [Project1] ORDER BY [Project1].[C1] DESC}

The sql query expected:

{SELECT 
[Project1].[C3] AS [C1], 
[Project1].[Label] AS [Label], 
[Project1].[C1] AS [C2], 
[Project1].[C2] AS [C3], 
[Project1].[C4] AS [C4]
FROM ( SELECT 
   [GroupBy1].[A1] AS [C1], 
   [GroupBy1].[A2] AS [C2], 
1 AS [C3], 
 CAST( 8 * [GroupBy1].[A3] AS float) - [GroupBy1].[A4] AS [C4], 
[GroupBy1].[K1] AS [Label]
FROM ( SELECT 
    [Extent2].[Label] AS [K1], 
    COUNT(1) AS [A1], 
    SUM([Extent1].[WorkedHours]) AS [A2], 
    COUNT(1) AS [A3], 
    SUM([Extent1].[WorkedHours]) AS [A4]
    FROM  [dbo].[Absences] AS [Extent1]
    RIGHT JOIN [dbo].[DepartementProjects] AS [Extent2] ON [Extent1].[DepartementProjectID] = [Extent2].[Id]
    WHERE N'SHT' = [Extent1].[Profil]
    GROUP BY [Extent2].[Label]
)  AS [GroupBy1]
)  AS [Project1] ORDER BY [Project1].[C1] DESC}

Solution

  •     var AbsByDepartmentADM = from department in _dbContext.DepartementProjects
                                  join abs in _dbContext.Absences on department.Id equals abs.DepartementProjectID into groupedResult
                                  from groupedResultRight in groupedResult.DefaultIfEmpty()
                                  group groupedResultRight by department.Label into grouped
                                  let NumberOfAbsence = grouped.Count(t => t.DepartementProjectID != null)
                                  let WorkedHours = grouped.Sum(a => a.WorkedHours != null ? a.WorkedHours : 0)
    
                                  select new
                                  {
                                      DepartmentId = grouped.Key,
                                      NumberOfAbsence,
                                      WorkedHours,
                                      AbsencesHours = (8 * NumberOfAbsence - WorkedHours)
                                  };