title: Using custom objects in JDBC insert statement
body: <p>I'll copy past a part from the mule website guide:</p>
  
  <pre><code>  &lt;jdbc:query key="outboundInsertStatement"
                value="INSERT INTO TEST (ID, TYPE, DATA, ACK) VALUES (#[map-payload:ID], 
                      #[map-payload:TYPE],#[map-payload:DATA], #[map-payload:ACK])"/&gt;
  </code></pre>
  
  <p>I am trying to do something very close to this only I want to use a custom object and not the <code>java.util.map</code> which i understand is what is expected.</p>
  
  <p>Could I get an explanation as to what does <code>#[map-payload:ACK]</code> exactly means? I dont understand the syntax.</p>
  
  <p>Is <code>map-payload</code> some sort of default type?</p>
  
  <p>Could I use that syntax to use a custom object I created? (Some <code>MesssageObj</code> class with some fields)</p>