title: Why does this dapper query return null?
body: <p>I have a mysql statement that I am passing to the dapper query method and it is returning a null object.  I have created a POCO class to hold the returned result.  I tested the query directly through a sql editor and it returned a result.  Here is the code:</p>
  
  <pre><code>public ViewEmail GetViewEmail(string xId, int headerId)
  {
      using (IDbConnection connection = new MySqlConnection(_connectionString))
      {
          string sql = "SELECT * FROM ViewEmail " +
                       "WHERE Header_id = @Header_id " +
                       "AND x_id= '@x_id'";
  
          var viewEmail = connection
              .Query&lt;ViewEmail&gt;(sql, new { Header_id = HeaderId, x_id = xId })
              .SingleOrDefault();
  
          return viewEmail;
      }
  }
  </code></pre>