title: Is it possible to "upsert" a message in Kafka using Kafka Connect?
body: <p>I am using Confluent 3.3.0. I am using <code>jdbc-source-connector</code> to insert messages into Kafka from my Oracle table. This works fine.<br>
  I would like to check if "upsert" is possible.</p>
  
  <p>I mean, if I have a student table, having 3 columns <code>id</code>(number), <code>name</code>(varchar2), and <code>last_modified</code>(timestamp). Whenever I insert new row, it will be pushed to Kafka (using timestamp+auto increment fields). But when I update the row, corresponding message in Kafka should be updated.  </p>
  
  <p>The <code>id</code> of my table should become they <code>key</code> of corresponding Kafka message. My primary key (id) will remain constant as a reference.<br>
  The Timestamp field will get updated every time when the row is updated.</p>
  
  <p>Is this possible? Or deleting existing record in Kafka and inserting the new one.</p>