title: Compare BLOB against other BLOBs in Oracle database
body: <p>How to check if there is a duplicate of a blob in a database. I have documents table in the database, however I'm not sure how to check if one of them has a duplicate. I know you're supposed to use dbms_lob.compare function but after reading a few threads and articles on the topic I still do not understand this.</p>
  
  <p>Documents table has document_id column and and data(blob) column. How can I possibly check if document_id = 1 has a duplicate?</p>