Joining 3 table in linq is it legal in C#

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I am struggling to call 3 tables in linq, can anyone help on this given logic. I am getting properties are not exist in current context.

What I have tried:

var list1 = (from w in db.Weeks  
             from p in db.ProductionDays on w.WeekId = p.WeekId  // Error here
             from m in db.Models on p.ProductionDate =  m.CreatedDate // Error here 
             where  
             (myModels.Contains(m.Name.ToString().ToUpper()))  
             select  
             {  
              w.Year,  
              w.WeekNum,  
              p.ProductionDate,  
              p.DayOfWeek,  
              m.Name,  
              m.Code,  
              m.InActive  
             }).ToList();

Posted 28-Apr-21 7:41am

Gcobani Mkontwana 2021

Updated 28-Apr-21 21:49pm

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Comments

[no name] 28-Apr-21 15:19pm

Do 2 "sets" at a time ... if it makes it easier to get your head around. (A "set" being a table, or the result of a "2 table" join).

(How do you think it gets done "under the covers"?)

George Swan 29-Apr-21 3:39am

Looks like you assigning w.WeelId to p.WeelId by using '=' when you should be using the equality operator '=='

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Richard Deeming · Accepted Answer · 2021-04-28T21:49:00

Solution 1

To join sets in LINQ, you use the join keyword, not the from keyword.
join clause - C# Reference | Microsoft Docs[^]

C#

from w in db.Weeks  
join p in db.ProductionDays on w.WeekId equals p.WeekId
join m in db.Models on p.ProductionDate equals m.CreatedDate

Posted 28-Apr-21 21:49pm

Richard Deeming