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c#linqjoinlambdasql-to-linq-conversion

Lambda Expression equivalent of "<>" in from clause of SQL with Join


Can anyone help me? I am not able to convert the following expression in the SQL to equivalent Lambda expression,

ON nextT.TaskID = a.NextTaskID AND a.TaskID <> nextT.TaskID 

SQL to be converted

SELECT a.*
FROM            dbo.Action AS a INNER JOIN dbo.Task AS t 
ON t .TaskID = a.TaskID 
INNER JOIN dbo.Task AS nextT 
ON nextT.TaskID = a.NextTaskID AND a.TaskID <> nextT.TaskID //This need to converted

My incomplete attempt to convert expression is as follows

Equivalent Lambda Expression

    var context = new DataClassesDataContext();
    var data = (from a in context.Actions
                join t in context.Tasks on a.TaskID equals t.TaskID
                join nextT in context.Tasks 
on 
.......new {v1 = a.NextTaskID, v2 = a.TaskID} equals new {v1 = nextT.TaskID , v2 = nextT.TaskID}.....<---This is the problem.
                select new vw_NextTask1
                {
                    TaskID = a.TaskID,
                    Task = t.Title,
                    ActionID = a.ActionID,
                    Action = a.Title,
                    NextPhaseID = a.NextPhaseID,
                    NextTaskID = nextT.TaskID,
                    NextTask = nextT.Title,
                          Type = a.Type
                }).ToList<vw_NextTask1>();
    return data;

Solution

  • you can add a where clause.

    var data = (from a in context.Actions
            join t in context.Tasks on a.TaskID equals t.TaskID
            join nextT in context.Tasks
            where nextT.TaskID != a.TaskID