David Gruzman questions

David Gruzman answers

• Hadoop (+HBase/HDFS) vs Mysql (or Postgres) - Loads of independent, structured data to be processed and queried
• How can I be sure that data is distributed evenly across the hadoop nodes?
• Can percentiles of a set of data be calculated in a map-reduce manner?
• Is something written to HDFS or Hbase visible to all other nodes in Hadoop Cluster immediately?
• Writing to a file in HDFS in Hadoop
• What are disadvantages of the Hadoop distribution MapR compared to Cloudera and Hortonworks? [closed]
• How does hive/hadoop assures that each mapper works on data that is local for it?
• What Are the Pros and Cons of Running a Job in Hadoop Using Various Languages?
• Sort reducer input iterator value before processing in Hadoop
• In Hadoop Map-Reduce, does any class see the whole list of keys after sorting and before partitioning?