Plusieurs tables de jointure gauche à l'aide de Linq

Je sais que le Linq jointure gauche comme ceci:

var q=from e in db.Employes    
      join o in db.Orders on e equals o.Emoloyee into ords  
      from on in ords.DefautIfEmpty()
      select new
      {      
         e.FirstName,     
         e.LastName   
      };

alors les multiples rejoindre? voici mon code

var personalInfoQuery = from t in crnnsupContext.Tombstones
                        join p in crnnsupContext.ProvStates on t.ProvinceState equals p.ProvinceStateID 
                        join n in crnnsupContext.NursingSchools on t.NursingSchool equals n.SchoolID 
                        join i in crnnsupContext.InitialEducations on t.InitialEducation equals SqlFunctions.StringConvert((double)i.InitalEducationID, 1)
                        join g in crnnsupContext.tbl_GraduatedProvCountry on t.GradPovCountry equals g.id
                        where t.RegNumber == _username
                        select new CPersonalInfo
                        {
                            ProvState = p,
                            Tombstone = t,
                            NursingSchool = n,
                            InitialEducation = i,
                            GraduatedProvCountry = g,
                         };

chaque table jointe pourrait avoir la valeur "null". peut m'aider, merci

OriginalL'auteur pita | 2012-06-06