title: Copying selected nodes and children with XLST
body: <p>I am having trouble with an XSLT transformation and I'm hoping someone could help me out. 
  Here is the structure of the data I am working with,</p>
  
  <pre><code>&lt;excelFiles&gt;
      &lt;sheet&gt;
          &lt;row index='1'&gt;
              &lt;column_1&gt;allowedValue&lt;/column_1&gt;
              &lt;column_2&gt;US&lt;/column_2&gt;
               &lt;column_3&gt;allowedValue&lt;/column_3&gt;
          &lt;/row&gt;
          &lt;row index='1'&gt;
             &lt;column_1&gt;notAllowedValue&lt;/column_1&gt;
             &lt;column_2&gt;US&lt;/column_2&gt;
             &lt;column_3&gt;allowedValue&lt;/column_3&gt;
          &lt;/row&gt;
    &lt;/sheet&gt;
  &lt;/excelFiles&gt;
  </code></pre>
  
  <p>What I am trying to do is only copy rows where none of the child nodes contain invalid data. Would this be possible with XSLT? I am constrained to only use XSLTto solve this issue.</p>
  
  <p>Edit for clarity: The invalid data is when the only value in the node is the '-' character.</p>