title: Query to check if field exists and then return the result set
body: <p>I dont know how can i explain it, may be this example garbage query can help.</p>
  
  <pre><code>SELECT if_exists(Fieldname) * FROM my table name
  </code></pre>
  
  <p>I am trying to select all the rows of the database only if <code>Fieldname</code> field is present.</p>
  
  <p>Can you help me out</p>