title: Oracle performance when updating millions of rows
body: <p>I'm trying to update almost 800 millions of rows and searching the best approach.
  I already tried to use bulk collection and update, but take to long.
  I commit after every 5000 records.
  For 130 min. I have only 0.25% ready, so I am searching another way.
  The structure of table is </p>
  
  <pre><code>CAMP_TASK                        NUMBER             
  CODE_SYSTEM                      VARCHAR2(10 CHAR)  
  ID_SOURCE                        VARCHAR2(40 CHAR)  
  ID_SOURCE_PARENT                 VARCHAR2(40 CHAR)  
  DATE_EFFECTIVE                   DATE               
  PROC_INSERTED                    NUMBER             
  PROC_UPDATED                     NUMBER             
  CAMP_TASK_PARENT                 NUMBER
  </code></pre>
  
  <p>and I have to update <code>camp_task_parent</code> field with camp_task value if id_source_parent is not null. So in other words if a have id_source_parent I have find his corresponding cam_task and update camp_task_parent with it for the current rowed.</p>
  
  <p>Thanks!</p>