title: Select rows with LINQ from List<Dictionary<string, object>>
body: <p>Lets assume simple data:</p>
  
  <pre><code>Dictionary&lt;string, object&gt; dict = new Dictionary&lt;string, object&gt;();
  dict.Add("obj 1", null);
  dict.Add("obj 2", new object());
  dict.Add("obj 3", new object());
  dict.Add("obj 4", null);
  
  Dictionary&lt;string, object&gt; dict2 = new Dictionary&lt;string, object&gt;();
  dict2.Add("obj 1", null);
  dict2.Add("obj 2", new object());
  dict2.Add("obj 3", null);
  dict2.Add("obj 4", null);
  
  Dictionary&lt;string, object&gt; dict3 = new Dictionary&lt;string, object&gt;();
  dict3.Add("obj 1", null);
  dict3.Add("obj 2", null);
  dict3.Add("obj 3", new object());
  dict3.Add("obj 4", null);
  
  List&lt;Dictionary&lt;string, object&gt;&gt; list = new List&lt;Dictionary&lt;string, object&gt;&gt; {dict, dict2, dict3};
  </code></pre>
  
  <p>Is it possible select rows and remove key/value where in all columns are null? So after this in my list will be:</p>
  
  <pre><code>dict({"obj 2", object}, {"obj 3", object})
  dict2({"obj 2", object}, {"obj 3", null})
  dict2({"obj 2", null}, {"obj 3", object})
  </code></pre>