title: How do I UPDATE a large table in oracle pl/sql in batches to avoid running out of undospace?
body: <p>I have a very large table (5mm records). I'm trying to obfuscate the table's VARCHAR2 columns with random alphanumerics for every record on the table. My procedure executes successfully on smaller datasets, but it will eventually be used on a remote db whose settings I can't control, so I'd like to EXECUTE the UPDATE statement in batches to avoid running out of undospace. </p>
  
  <p>Is there some kind of option I can enable, or a standard way to do the update in chunks?</p>
  
  <p>I'll add that there won't be any distinguishing features of the records that <em>haven't</em> been obfuscated so my one thought of using rownum in a loop won't work (I think).</p>