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Showing posts with the label hadoop

Processing CSV Files using Hive / Hadoop / HDFS

Background When there is a need to process large-sized CSV files, Apache Hive became a good option since it allow us to directly query these files. I will try to describe my recent experiences in using Apache Hive. In this case I need to group the rows and count the rows for each group. I will compare to my existing systems using MySQL database, one built using PHP and other built using combination of Pentaho and PHP. Installation & Configuration We have many components of Hadoop-Hive-HDFS ecosystem : HDFS : Namenode service, Datanode services.  MapReduce : ResourceManager service, NodeManager services Hive  ZooKeeper Each component have their own configuration file (or files), and their own log files.  For simplicity, in my opinion nothing beats the Apache-MySQL-PHP stack. Minus points for Hadoop-Hive-HDFS in complexity standpoint. I think we need additional management layer to be able to cope with complexity, maybe like Cloudera Manager or Apac...

First steps with Hadoop

Background I need some improvement in one of the batch processes I run. It were build using PHP, parsing text files into mysql database. So for a change I tried to learn Hadoop and Hive Installation 1 Hadoop is a bit more complex than MySQL installation. Ok, so 'a bit' is an understatement. I tried to follow Windows installation procedure from HadoopOnWindows . I downloaded the binary package instead of the source package, because I am not in the mood of waiting mvn downloading endless list of jars. Well, some errors prevented me from continuing this path. Installation 2 Virtual machines seems to be way to go. Not wanting to spend too much time installing and configuring VMs, I installed Vagrant, a tool to download images and configure VMs automatically. VirtualBox is required as Vagrant's default provider, so I installed it too. At first I tried to follow this blog post titled Installing a Hadoop Cluster in Three Commands , but it somehow doesn't work eith...