title: Export data from database and write to HDFS(hadoop fs)
body: <p>Now i am trying to export data from a db table, and write it into hdfs.</p>
  
  <p>And the problem is: will the name node become bottleneck? and how is the machanism, will name node cache a slice(64MB) and then give it to data node?</p>
  
  <p>And is there any better way rather than write the hdfs? because i think it dosen't take the advantage of parellism.</p>
  
  <p>Thanks:)</p>