title: Linq join on multpile columns with a where not equals condition and need to return columns from both tables
body: <p>I am joining tables on two columns and need to find records where the third column does not match. </p>
  
  <p>The linq query I have will return the correct records from table 1, but I am unable to select the date column from the second table. </p>
  
  <p>I have tried grouping results but had trouble with the 'where not equals' condition. </p>
  
  <p>So, I have these records:</p>
  
  <p><strong>Table 1:</strong> <em>4SONS, 112, 09/03/2016</em></p>
  
  <p><strong>Table 2:</strong> <em>4SONS, 112, 09/26/2016</em></p>
  
  <p>What I need to return is - <em>4SONS, 112, 09/03/2016, 09/26/2016</em></p>
  
  <p>But my query returns only - <em>4SONS, 112, 09/03/2016</em> without a way to get that date from table 2. These are the only 3 columns in each table. </p>
  
  <pre><code>var query = from s in schedTable.AsEnumerable()
              where s.Field&lt;DateTime?&gt;("AuditDate").HasValue
  
              join c in completeTable.AsEnumerable()
              on new { account = s.Field&lt;string&gt;("Account").ToString(), store = s.Field&lt;string&gt;("Store").ToString()} 
              equals new { account = c.Field&lt;string&gt;("Account").ToString(), store = c.Field&lt;string&gt;("Store").ToString() }
  
              where s.Field&lt;DateTime&gt;("AuditDate").Date != c.Field&lt;DateTime&gt;("AuditDate").Date
              select s;
  
  var typeD = query.ToList();
  </code></pre>