title: Fetch all rows in cassandra
body: <p>I have a cassandra table containing 3 million rows. Now I am trying to fetch all the rows and write them to several csv files. I know it is impossible to perform <code>select * from mytable</code>. Could someone please tell how I can do this?</p>
  
  <p>Or are there any ways to read the rows <code>n</code> rows by <code>n</code> rows without specifying any <code>where</code> conditions?</p>