title: Linq to Sql isnull in where clause not working
body: <p>I have Linq query as:</p>
  
  <pre><code>var notstartedcount = (from te in context.EH_PP_TeacherEvaluations
                         join tesrt in context.EH_PP_TeacherEvaluationStatusesRefTables
                         on te.EH_PP_TESRT_TeacherEvalStatusID equals 
                            tesrt.EH_PP_TESRT_TeacherEvalStatusID
                         where tesrt.EH_PP_TESRT_TeacherEvalStatusID.Equals("1") || 
                               tesrt.EH_PP_TESRT_TeacherEvalStatusID.Equals("")
                         select te).Count();
  </code></pre>
  
  <p>I just wanted to put <code>Isnull(ColumnName,replacement)</code> in where condition as we do it in Sql.</p>
  
  <p>Eg.:</p>
  
  <pre><code>where isNull(EH_PP_TESRT_TeacherEvalStatusID,0)=1
  </code></pre>
  
  <p>I kept same condition for linq as:</p>
  
  <pre><code>var notstartedcount = (from te in context.EH_PP_TeacherEvaluations
                         join tesrt in context.EH_PP_TeacherEvaluationStatusesRefTables
                         on te.EH_PP_TESRT_TeacherEvalStatusID equals 
                            tesrt.EH_PP_TESRT_TeacherEvalStatusID
                         where 
                             isnull(tesrt.EH_PP_TESRT_TeacherEvalStatusID.Equals(Null),0).Equals("1") || 
                             tesrt.EH_PP_TESRT_TeacherEvalStatusID.Equals("")
                         select te).Count();
  </code></pre>
  
  <p>But its error in case of linq.</p>
  
  <p>How can i put that condition into it?</p>