title: How to find type of blob file
body: <p>I have oracle db, with have column with blob files.</p>
  
  <p>I getting data from table and i need to show data and blob in form.</p>
  
  <p>Blob can be PDFs or images.. </p>
  
  <p>My question are how to know what is in blob,are that image , pdf or something third?</p>
  
  <p>Thanx </p>