title: regex to convert alphanumeric and special characters in a string to * in oracle
body: <p>I have a requirement to convert all the characters in my string to <code>*</code>. My string can also contain special characters as well.</p>
  
  <p>For Example:<br>
  <code>abc_d$</code> should be converted to <code>******</code>.</p>
  
  <p>Can any body help me with <code>regex</code> like this in <code>oracle</code>.  </p>
  
  <p>Thanks</p>