LINQ Error when using multiple JOIN in same statement on CRM 2011 Plug-in

Question

Hi I am trying to join multiple entities in CRM 2011 but I get and error saying: {"'xrmsm_sessionEnrollments' entity doesn't contain attribute with Name = 'xrmsm_termsid'."}. That is correct but I am joining the entity that have that attribute.

My Linq Query:

var query2 = from e in svsContext.xrmsm_sessionEnrollmentsSet

        join s in svsContext.xrmsm_sessionsSet on e.xrmsm_SessionLookup.Id equals s.xrmsm_sessionsId
        join ic in svsContext.xrmsm_institutionCoursesSet on s.xrmsm_institutionCourseLookup.Id equals ic.xrmsm_institutionCoursesId
        join ts in svsContext.xrmsm_term_sessionsSet on e.xrmsm_termSessionLookup.Id equals ts.xrmsm_term_sessionsId
        join t in svsContext.xrmsm_termsSet on ts.xrmsm_TermLookup.Id equals t.xrmsm_termsId
        where (e.xrmsm_StudentLookup.Equals(studentlookup)
               && e.xrmsm_YearLookup.Equals(entity.GetAttributeValue("xrmsm_studentlookup"))
               && ic.xrmsm_institutionCoursesId == institutionCourseGuid
               && t.xrmsm_termsId == termGuid)
        select new { sessionName = s.xrmsm_sessionsName, StudentName = e.xrmsm_studentsName, StudentId = e.xrmsm_StudentLookup.Name };

My original SQL query that works on SQL Server:

SELECT en.xrmsm_currentsessionenrollmentsname
      ,en.xrmsm_isreadonlyname
      ,en.xrmsm_sessionenrollmentsaverage
      ,en.xrmsm_sessionenrollmentsgrade
      ,en.xrmsm_sessionenrollmentsid
      ,en.xrmsm_sessionenrollments_id
      ,en.xrmsm_sessionlookup as sessionid
      ,en.xrmsm_sessionlookupname
      ,en.xrmsm_sessionsname
      ,en.xrmsm_studentlookup AS studentid
      ,en.xrmsm_studentlookupname
      ,en.xrmsm_studentsname
      ,en.xrmsm_termsessionlookup
      ,en.xrmsm_termsessionlookupname
      ,en.xrmsm_withdrawal
      ,en.xrmsm_yearaverage
      ,en.xrmsm_yeargrade
      ,en.xrmsm_yearlookup
      ,en.xrmsm_yearlookupname
  FROM CoseyTest_MSCRM.dbo.Filteredxrmsm_sessionEnrollments as en INNER JOIN 
  CoseyTest_MSCRM.dbo.Filteredxrmsm_sessions crmsessions ON 
  (en.xrmsm_sessionlookup = crmsessions.xrmsm_sessionsid AND en.xrmsm_yearlookup = crmsessions.xrmsm_yearlookup)
  INNER JOIN Filteredxrmsm_institutionCourses institutionCourses
  on crmsessions.xrmsm_institutioncourselookup = institutionCourses.xrmsm_institutioncoursesid
  Inner Join Filteredxrmsm_term_sessions as termsession
  on en.xrmsm_termsessionlookup = termsession.xrmsm_term_sessionsid
  Inner Join Filteredxrmsm_terms as terms
  on termsession.xrmsm_termlookup = terms.xrmsm_termsid 
  where en.xrmsm_yearlookup = '4BA07BED-3F51-E211-8359-00155D004403' 
  and en.xrmsm_studentlookup = 'C844AF65-5B51-E211-8359-00155D004403'
  and terms.xrmsm_termsid = 'D1D107B7-4551-E211-8359-00155D004403' 
  and institutionCourses.xrmsm_institutioncoursesid = '2121914E-4551-E211-8359-00155D004403'

Answer 1

Thanks for all your responses. I did the following workaround.

1. Make a query that retrieve a list of all the Student enrollments

2. Use the Find method of the List<T> class to find if a record exist with the conditions I am searching for.

    var query2 = (from e in svsContext.xrmsm_sessionEnrollmentsSet
                    join s in svsContext.xrmsm_sessionsSet on e.xrmsm_SessionLookup.Id equals s.xrmsm_sessionsId
                    join ic in svsContext.xrmsm_institutionCoursesSet on s.xrmsm_institutionCourseLookup.Id equals ic.xrmsm_institutionCoursesId
                    join ts in svsContext.xrmsm_term_sessionsSet on e.xrmsm_termSessionLookup.Id equals ts.xrmsm_term_sessionsId
                    join t in svsContext.xrmsm_termsSet on ts.xrmsm_TermLookup.Id equals t.xrmsm_termsId
                    where (e.xrmsm_StudentLookup.Equals(studentlookup))
                    select new
                    {
                        EnrollmentId = e.xrmsm_sessionEnrollments_id,
                        SessionId = s.xrmsm_sessions_id,
                        EnrollmentYear = e.xrmsm_YearLookup,
                        InstitutionCourseId = (Guid)ic.xrmsm_institutionCoursesId,
                        TermId = (Guid)t.xrmsm_termsId,
                        Student = e.xrmsm_StudentLookup
                    }).ToList();
   
   
       var q = query2.Find(r => r.EnrollmentYear.Id == entity.GetAttributeValue<EntityReference>("xrmsm_yearlookup").Id
                            && r.InstitutionCourseId == institutionCourseGuid
                            && r.TermId == termGuid);
   

Answer 2

Linq provider for CRM has some limitations. You can fount it here. Check if your query violates limitations.

Answer 3

Try having a look at the actual query that it is generating and run that in SQL, it may help understand what is going on.

It could be that something your doing in LINQ is not available in CRM as paramosh mentioned but I can't see anything that jumps out at me.