title: Find and replace string inside BLOB for Work or Excel File
body: <p>I have a requirement to find and replace hyperlinks which are outdated in several thousand documents stored in the database.</p>
  <p>Currently I have some functions that will covert a BLOB to a CLOB do a find and replace and then convert back to a BLOB.</p>
  <p>The end results however don't leave the file in its original state e.g. I have a word doc stored I find hyperlink <a href="http://www.google.co.uk" rel="nofollow noreferrer">www.google.co.uk</a> and replace and the BLOB data is no longer of type word document and I can't open it.</p>
  <p>Is there a recommended method to do the above.</p>
  <p>Many Thanks,</p>